The field of imaging technology began in 1895 with the discovery of

Question

The field of imaging technology began in 1895 with the discovery of x—rays, which first allowed physicians to peer into their patients without surgery. In recent decades there have been enormous advances in imaging technology; not only have x—ray techniques been vastly improved, but new methods, especially computed tomography, have been introduced. Although there has been some debate, most doctors agree that each imaging technique possesses some property that makes it uniquely useful, and no single method has prevailed to the exclusion of others.

X—rays remain the most widely used imaging technique. The technique consists of irradiating the relevant part of the body with an x—ray source and allowing the x—rays that are transmitted to strike an x-ray-sensitive fluorescent screen, which then balkens a sheet of light—sensitive film, thereby producing a two—dimensional image of a three—dimensional structure. Today fluorescent screen film combinations can register more than 60 percent of the radiation striking them. Consequently, even fairly small differences in the distribution of the transmitted x—rays can be discerned. Although film techniques are very effective for imaging parts of the body with high contrast, such as lungs and bones, they are limited in their capacity for imaging organs of low contrast, such as kidneys and gallbladders. The great advantage of film techniques is the relatively short time it takes to acquire a complete image, and the consequent high rate at which images can be repeated—uup to 60 times per second, an advantage for viewing the heart and other rapidly moving organs.

Computed tomography (CT) offers a most exciting refinement in producing a visual image of body organs. Instead of compressing a three—dimensional structure into a two-dimensional image, CT uses an extremely narrow beam to produce a sequence of profiles that can be combined into an image, or tomogram, of a thin slice of the body. These images are more readily comprehended than conventional x—ray images because confusion caused by superimposition is eliminated, and because the narrowness of the beam markedly decreases the registration of scattered rays, thus improving the image contrast.

CT imaging is more time—consuming than imaging on film, because irradiation and data acquisition usually take a relatively slow 2 to 10 seconds per slice and, without special computers, the mathematical process for reconstructing the image requires another 15 to 30 seconds. CT also requires that the body be viewed as a series of many individual slices, but it has the unique attribute of being sensitive to extremely slight contrast differences in tissue — it can, for example, discriminate between white and gray matter in the brain. For this reason, CT has proved invaluable for imaging the brain, for diagnosing hemorrhage and stroke, and for evaluating certain kinds of cancers.    1 
 1. Which of the following best summarizes the author's main point?

(A) The introduction of x—ray techniques into medicine virtually revolutionized the field.
(B) Without replacing x—ray techniques, the development of CT has widened the scope of imaging technology
(C) Although CT has many virtues, it has some major drawbacks as well
(D) Imaging techniques have permitted physicians to diagnose many internal disorders without surgery.
(E) The most important factor in assessing the value of imaging techniques is speed.

2 
 2. According to the passage, all of the following are true about conventional x—ray imaging EXCEPT that it

(A) was the first imaging technique invented
(B) is the most popular of the imaging techniques
(C) records virtually all transmitted radiation
(D) produces images rapidly
(E) was developed after 1894

3 
 3. It can be inferred from the passage that in conventional x—ray imaging one characteristic of the beam is that it

(A) undergoes significant scattering on transmission through the body
(B) is accurately maintained at an extremely narrow width
(C) requires a great deal of energy to operate
(D) can be moved rapidly from one part of the body to another
(E) is mostly absorbed by the tissue of the body

4 
 4. It can be inferred from the passag that one purpose of the fluorescent screen in conventional x—ray imaging is to

(A) monitor the amount of radiation the patient has received
(B) hold in place the light-sensitive film for the X—ray image
(C) allow the physician to judge immediately the quality of the X—ray image
(D) produce an image of the irradiated organ for the film
(E) control the speed at which an image is produced

5 
 5. According to the passage, CT imaging has been particularly useful for

(A) imaging the lungs
(B) analyzing some cancers
(C) diagnosing bone injuries
(D) observing the muscles of the heart during contraction
(E) studying the motions of the stomach during digestion

6 
 6. The passage would most likely appear in a

(A) science magazine for nonspecialists
(B) textbook on radiation physics
(C) medical research journal
(D) CT users' manual
(E) monograph on early twentieth—century medical technology

7 
 7. It can be inferred from the passage that CT is extremely valuable for imaging the brain primarily because

(A) tomograms of the brain give the best picture of the activities of the brain
(B) the brain is composed of tissues whose contrast differences are not very great
(C) only relatively slow imaging techniques can produce medically useful images of the brain
(D) better images can be constructed out of profiles of the relatively small brain than out of profiles of larger areas of the body
(E) x—rays are unable to penetrate the skull sufficiently to obtrain a sharp picture of the brain

8 
 8. Which of the following ways of obtaining information is most like CT imaging?

(A) Learning about a house by looking in the front door
(B) Studying an orange by peeling it
(C) Characterizing a crystal by measuring the angle between two faces
(D) Studying a tree trunk by making slices through the trunk
(E) Learning about a coconut by drilling a hole in it

8Harshitsharma · Answer

Quick notes:
P1: intro of x-ray started the imaging technique field. most doctors think all imaging techs should be kept for their exclusive functionality.
P2: pros of x-ray, some cons.
P3: pros of CT.
P4: cons and again pros of CT.
 
Tricky choices B and D. Both seem correct.
 A. Too narrow. Only in the 1st para. 
 B. This essentially captures all the aspects mentioned in passage - x-ray pros, cons and CT development and advantages. 
 C. Too narrow.
D. This could be an over-arching idea if this question would've been asked in some other exam, but GMAT needs a specific answer even for a general question like main point. INCORRECT.
E. Too specific. 
 
   A. True. See Para 1.
B. True. See Para 2. 
 C. False. See Para 2. Only 60% is recorded. 
 D. True. See Para 2.
E. True. See Para 1.   
 
   A. significant here means - statistically significant to make it possible to see the difference on the film. 
 B. Nope - it's CT
C. Not stated
D. Not stated
E. Not stated   
 
 A. Incorrect.
B. Incorrect.
C. Incorrect. 
 D. Correct. See Para 2. 
 E. Incorrect. 
 
 A. Nope. 
 B. Yes, see the last sentence of the passage. 
 C. Nope.
D. Nope. 
E. Nope. 
 
Hard to choose between A & C - both seem appropriate to include this discussion.

A. The technicalities of the machines and technology discussed make it apt for a science magazine. 
 B. No we didn't even go into details about radiation or its effects, characteristics etc.
C. Hmmm, seems close but I would say there is not enough medical terms or diseases discussed to qualify it for this.
D. Nope
E. The technology discussed is recent, even though the passage starts with the early technology in para 1.     
 
 A. Not the "best" picture claim again - we don't know if it's the best, we only know it's good. 
 B. Correct. See para 3 middle portion. 
 C. Not stated.
D. No details about profiling are discussed.
E. Not stated. 
 
Per para 3, CT produces a cross-sectional image of a slice of brain, which identifies even areas with slight contrast differences.

A. Wth, you can even do that??!! - not with CT though. This sounds more like a regular health checkup. lol.
B. Nope - more like surgery.
C. Not at all. 
 D. Nailed it. 
 E. Omg, drilling a hole in the head to learn about it. Sounds awfully scary. Thank God it is not what CT does.

missionmba2025 · Answer

1. Which of the following best summarizes the author's main point?

The passage starts by introducing the concept of imaging technology and then talks about two technologies - X-Ray and CT. The second line of the first paragraph provides us a clue - " In recent decades there have been enormous advances in imaging technology; not only have x—ray techniques been vastly improved, but new methods, especially computed tomography, have been introduced. " - that the passage is likely going to explain us about computed tomography.

(A) The introduction of x—ray techniques into medicine virtually revolutionized the field.

While the passage does mention about CT Scans this is not the the primary purpose. The introduction to X-Ray was only to create a base for the passage.

(B) Without replacing x—ray techniques, the development of CT has widened the scope of imaging technology

This is indeed a correct option. The passage opens with the concept of X-Rays but then goes about explaining how Computed tomography (CT) offers an advancement in producing a visual image of body organs.

(C) Although CT has many virtues, it has some major drawbacks as well

The passage doesn't contrast anything on the CT scans. Hence, this is an incorrect option.

(D) Imaging techniques have permitted physicians to diagnose many internal disorders without surgery.

While this is true and the passage opens with this idea, the main purpose of the passage is not to convey this message.

(E) The most important factor in assessing the value of imaging techniques is speed.

This is not correct. The reference to speed is done only to explain CT scans and X-Rays.

2. According to the passage, all of the following are true about conventional x—ray imaging EXCEPT that it

(A) was the first imaging technique invented

Correct. Refer to the part of the passage " which first allowed physicians to peer into "

(B) is the most popular of the imaging techniques

Correct. Refer to the part of the passage " remain the most widely used imaging technique "

(C) records virtually all transmitted radiation

This is incorrect. The passage mentions " can register more than 60 percent of the radiation striking them ". Hence x-ray cannot record all transmitted radiations.

(D) produces images rapidly

Correct. Refer to the part of the passage " The great advantage of film techniques is the relatively short time it takes to acquire a complete image "

(E) was developed alter 1894

Correct. Refer to the part of the passage " The field of imaging technology began in 1895 "

3. It can be inferred from the passage that in conventional x—ray imaging one characteristic of the beam is that it

(A) undergoes significant scattering on transmission through the body

This is a correct option. The passage mentions " can register more than 60 percent of the radiation striking them ". This means some of the x-ray is lost (scattered). Hence, this information is inline with the detail mentioned in the passage.

(B) is accurately maintained at an extremely narrow width

This information is in reference to CT scans. Eliminate B.

(C) requires a great deal of energy to operate

No information is mentioned with respect to the energy used in x-ray imaging. Hence, we can eliminate this option.

(D) can be moved rapidly from one part of the body to another

The passage mentions that the images can be repeated. Refer " images can be repeated—uup to 60 times per second ". The passage doesn't mention that the x-ray imaging can be moved from one part of the body to another. This is incorrect.

(E) is mostly absorbed by the tissue of the body

No information on the abosorption is mentioned in the passage. Hence, this option is incorrect.

4. It can be inferred from the passag that one purpose of the fluorescent screen in conventional x—ray imaging is to

(A) monitor the amount of radiation the patient has received

This is incorrect. The screen captures the rays, not monitors.

(B) hold in place the light-sensitive film for the X—ray image

This is not correct. The information provided in the passage doesn't state anything on the amount of light held. Hence, we can eliminate this option.

(C) allow the physician to judge immediately the quality of the X—ray image

No such information is provided in the passage. Hence, we can eliminate C.

(D) produce an image of the irradiated organ for the film

This is inline with the details mentioned in the passage " hereby   producing   a two—dimensional image of a three—dimensional structure".  Hence, the fluorescent screen in conventional x—ray imaging is responsible for creating an image of the organ.

(E) control the speed at which an image is produced

This is not correct. The speed at which image is produced is not controlled by the fluorescent screen.

5. According to the passage, CT imaging has been particularly useful for

The answer to this question is mentioned in the last line of the passage " and for evaluating certain kinds of cancers "

(A) imaging the lungs

Incorrect. Eliminate A.

(B) analyzing some cancers

True, as mentioned above the details is mentioned in the passage.

(C) diagnosing bone injuries

Incorrect. The passage doesn't mention this information.

(D) observing the muscles of the heart during contraction

The reference to heart in the passage is for x-rays. Eliminate D.

(E) studying the motions of the stomach during digestion

No such information is provided in the passage. Hence, eliminate E.

6. The passage would most likely appear in a

(A) science magazine for nonspecialists

This seems correct. The information is simple enough and doesn't delve into technicalities of x-ray or CT scan.

(B) textbook on radiation physics

The details presented on the passage is not limited to radiation. The information presented is generic. Eliminate B.

(C) medical research journal

The details mentioned in the passage is not of research nature, i.e. the passage doesn't mention of an experiment or conclusion that anyone has made. Hence, we can eliminate this.

(D) CT users' manual

This is incorrect. The details presented the passage is non technical. Hence, such information cannot be a part of the user manual.

(E) monograph on early twentieth—century medical technology

This doesn't seem to be the case. We can eliminate this option.

7. It can be inferred from the passage that CT is extremely valuable for imaging the brain primarily because

The answer to this question lies in " but it has the   unique attribute of being sensitive to extremely slight contrast differences in tissue   — it can, for example, discriminate between white and gray matter in the brain "

(A) tomograms of the brain give the best picture of the activities of the brain

The passages doesn't mention that tomograms gives the best picture. The passage merely compares the images produced by CT scans with X-rays. Hence, we can eliminate A.

(B) the brain is composed of tissues whose contrast differences are not very great

This is correct. The highligted part mentions that information.

(C) only relatively slow imaging techniques can produce medically useful images of the brain

This is not correct. We can eliminate C.

(D) better images can be constructed out of profiles of the relatively small brain than out of profiles of larger areas of the body

No such information can be inferred from the passage. We can eliminate D.

(E) x—rays are unable to penetrate the skull sufficiently to obtrain a sharp picture of the brain

No such details is presented in the passage. We can eliminate E.

8. Which of the following ways of obtaining information is most like CT imaging?

(A) Learning about a house by looking in the front door

This is incorrect. CT scans registers the images in layers. Hence, we can eliminate A.

(B) Studying an orange by peeling it

This option is a tricky one. While the option talks about layers, CT scans registers the body as thin indivdual slices. The option is close, but D seems better.

(C) Characterizing a crystal by measuring the angle between two faces

This is not correct. We can eliminate C.

(D) Studying a tree trunk by making slices through the trunk

This is correct. Refer to the last paragraph " CT also requires that the body be viewed as a series of many   individual slices  , but it has the unique attribute of being sensitive to extremely slight contrast differences in tissue "

(E) Learning about a coconut by drilling a hole in it

Incorrect. CT scans views the body as series of layers. Hence, we can eliminate this option.

Answers
1. B
2. C
3. A
4. D
5. B
6. A
7. B
8. D

Oppenheimer1945 · Answer

P1: Imaging Tech is discussed ... advantages of these methods have come up with newer updates
P2: X-ray imaging is discussed with process details and advantages
P3: CT method is is discussed with process details and advantages over X-ray method
P4: Disadvantages & specific advantages of CT method over X_ray method is discussed

1. Which of the following best summarizes the author's main point?
(A) The introduction of x—ray techniques into medicine virtually revolutionized the field.(part of passage)
 (B) Without replacing x—ray techniques, the development of CT has widened the scope of imaging technology (True) 
(C) Although CT has many virtues, it has some major drawbacks as well (fragment of passage)
(D) Imaging techniques have permitted physicians to diagnose many internal disorders without surgery. (Intro of passage)
(E) The most important factor in assessing the value of imaging techniques is speed. (irrelevant)

2. According to the passage, all of the following are true about conventional x—ray imaging EXCEPT that it

(A) was the first imaging technique invented (P1 Line 1)
(B) is the most popular of the imaging techniques (P2 Line 2)
 (C) records virtually all transmitted radiation (Today fluorescent screen film combinations can register more than 60 percent of the radiation striking them) 
(D) produces images rapidly (The great advantage of film techniques is the relatively short time it takes to acquire a complete image,)
(E) was developed alter 1894 (P1 Line 1)

Today fluorescent screen film combinations can register more than 60 percent of the radiation striking them

3. It can be inferred from the passage that in conventional x—ray imaging one characteristic of the beam is that it
(A) undergoes significant scattering on transmission through the body
(B) is accurately maintained at an extremely narrow width
(C) requires a great deal of energy to operate
(D) can be moved rapidly from one part of the body to another
 (E) is mostly absorbed by the tissue of the body (True)

x-ray-sensitive fluorescent screen, which then balkens a sheet of light—sensitive film, thereby producing a two—dimensional image of a three—dimensional structure.

4. It can be inferred from the passag that one purpose of the fluorescent screen in conventional x—ray imaging is to

(A) monitor the amount of radiation the patient has received
(B) hold in place the light-sensitive film for the X—ray image
(C) allow the physician to judge immediately the quality of the X—ray image
 (D) produce an image of the irradiated organ for the film (True) 
(E) control the speed at which an image is produced

For this reason, CT has proved invaluable for imaging the brain, for diagnosing hemorrhage and stroke, and for evaluating certain kinds of cancers.

5. According to the passage, CT imaging has been particularly useful for

(A) imaging the lungs
 (B) analyzing some cancers (True) 
(C) diagnosing bone injuries
(D) observing the muscles of the heart during contraction
(E) studying the motions of the stomach during digestion

Passage talks about a scientific method...

6. The passage would most likely appear in a
 (A) science magazine for nonspecialists (True) 
(B) textbook on radiation physics (radiation is very specific)
(C) medical research journal (irrelavant)
(D) CT users' manual (very sepcific)
(E) monograph on early twentieth—century medical technology (early 20th century can't be concluded. its late 19th century)

it has the unique attribute of being sensitive to extremely slight contrast differences in tissue

7. It can be inferred from the passage that CT is extremely valuable for imaging the brain primarily because

(A) tomograms of the brain give the best picture of the activities of the brain
 (B) the brain is composed of tissues whose contrast differences are not very great (true) 
(C) only relatively slow imaging techniques can produce medically useful images of the brain
(D) better images can be constructed out of profiles of the relatively small brain than out of profiles of larger areas of the body
(E) x—rays are unable to penetrate the skull sufficiently to obtrain a sharp picture of the brain

CT also requires that the body be viewed as a series of many individual slices,

8. Which of the following ways of obtaining information is most like CT imaging?

(A) Learning about a house by looking in the front door
(B) Studying an orange by peeling it
(C) Characterizing a crystal by measuring the angle between two faces
 (D) Studying a tree trunk by making slices through the trunk (true) 
(E) Learning about a coconut by drilling a hole in it

mayankdgmat · Answer

1. Which of the following best summarizes the author's main point?

IMO B

(A) The introduction of x—ray techniques into medicine virtually revolutionized the field.
Author also discussed CT. Out

(B) Without replacing x—ray techniques, the development of CT has widened the scope of imaging technology
True, CT has been advantageous at certain time.

(C) Although CT has many virtues, it has some major drawbacks as well
Focus is not only on CT, but imaging as a whole

(D) Imaging techniques have permitted physicians to diagnose many internal disorders without surgery.
This is one of advantage discussed but not main point.

(E) The most important factor in assessing the value of imaging techniques is speed.
No where it is mentioned, CT is slower than X-ray but indispensable in some cases.

2. According to the passage, all of the following are true about conventional x—ray imaging EXCEPT that it

IMO C

Mentioning relevant part of passage in each answer choice which shows why it is true or false.

(A) was the first imaging technique invented
"The field of imaging technology began in 1895 with the discovery of x—rays"

(B) is the most popular of the imaging techniques
"X—rays remain the most widely used imaging technique"

(C) records virtually all transmitted radiation
"Today fluorescent screen film combinations can register more than 60 percent of the radiation striking them"

(D) produces images rapidly
"The great advantage of film techniques is the relatively short time it takes to acquire a complete image"

(E) was developed alter 1894
"The field of imaging technology began in 1895 with the discovery of x—rays"

3. It can be inferred from the passage that in conventional x—ray imaging one characteristic of the beam is that it

IMO A

(A) undergoes significant scattering on transmission through the body
True can be deduced from "These images are more readily comprehended than conventional x—ray images because confusion caused by superimposition is eliminated, and because the narrowness of the beam markedly decreases the registration of scattered rays, thus improving the image contrast"

(B) is accurately maintained at an extremely narrow width
That is property of CT

(C) requires a great deal of energy to operate
Nowhere mentioned.

(D) can be moved rapidly from one part of the body to another
Beam can be moved?? no wrong

(E) is mostly absorbed by the tissue of the body
Mostly absobed on screen which is more than 60%.

4. It can be inferred from the passag that one purpose of the fluorescent screen in conventional x—ray imaging is to

IMO D

(A) monitor the amount of radiation the patient has received
No screen receive irradiated beams from organ

(B) hold in place the light-sensitive film for the X—ray image
No it is recieving beams

(C) allow the physician to judge immediately the quality of the X—ray image
Quality not discussed

(D) produce an image of the irradiated organ for the film
Yes, "he technique consists of irradiating the relevant part of the body with an x—ray source and allowing the x—rays that are transmitted to strike an x-ray-sensitive fluorescent screen, which then balkens a sheet of light—sensitive film, thereby producing a two—dimensional image of a three—dimensional structure."

(E) control the speed at which an image is produced. 
No mention about speed. only generally it is mentioned that x-ray produced image faster than CT

5. According to the passage, CT imaging has been particularly useful for

IMO B

(A) imaging the lungs
Out because passage says "Although film techniques are very effective for imaging parts of the body with high contrast, such as lungs and bones,"

(B) analyzing some cancers
True. "CT has proved invaluable for imaging the brain, for diagnosing hemorrhage and stroke, and for evaluating certain kinds of cancers."

(C) diagnosing bone injuries
"Although film techniques are very effective for imaging parts of the body with high contrast, such as lungs and bones,"

(D) observing the muscles of the heart during contraction
This is wrong, this can be done by X-ray. "the consequent high rate at which images can be repeated—uup to 60 times per second, an advantage for viewing the heart and other rapidly moving organs."

(E) studying the motions of the stomach during digestion
No mention.

6. The passage would most likely appear in a

IMO B

(A) science magazine for nonspecialists
Not most likely, may be for nonspecialists or not we are not sure.

(B) textbook on radiation physics
Yes passage discussing imaging which is branch of radilogy

(C) medical research journal
No research presented

(D) CT users' manual
How to use CT machine not discussed.

(E) monograph on early twentieth—century medical technology
it discusse a particular medical tech, hence out

7. It can be inferred from the passage that CT is extremely valuable for imaging the brain primarily because

IMO B

(A) tomograms of the brain give the best picture of the activities of the brain
It's not about picture, it's about crossing hurdle of differntating color contrast

(B) the brain is composed of tissues whose contrast differences are not very great
Passage says it works where it is difficult to differentiate bw colors"but it has the unique attribute of being sensitive to extremely slight contrast differences in tissue — it can, for example, discriminate between white and gray matter in the brain. For this reason, CT has proved invaluable for imaging the brain"

(C) only relatively slow imaging techniques can produce medically useful images of the brain
No, issue of color contrast with X-ray not speed

(D) better images can be constructed out of profiles of the relatively small brain than out of profiles of larger areas of the body
No comparison bw small brain with large area of the body

(E) x—rays are unable to penetrate the skull sufficiently to obtrain a sharp picture of the brain
No where it is mentioned that it can't pentrate

8. Which of the following ways of obtaining information is most like CT imaging?

Need to find structure parallel to "CT also requires that the body be viewed as a series of many individual slices, but it has the unique attribute of being sensitive to extremely slight contrast differences in tissue"

IMO D

(A) Learning about a house by looking in the front door
Not parallel to above structure

(B) Studying an orange by peeling it
Not parallel to above structure

(C) Characterizing a crystal by measuring the angle between two faces
Not parallel to above structure

(D) Studying a tree trunk by making slices through the trunk
parallel to above structure

(E) Learning about a coconut by drilling a hole in it
Not parallel to above structure

Anugmat740 · Answer

1. Which of the following best summarizes the author's main point? 
P1: Introduction about Imaging techniques with the X-rays
P2: How x-ray works and their limitations
P3: Introduction about CT and why they need over X-rays
P4: Advantage of CT.

(A) The introduction of x—ray techniques into medicine virtually revolutionized the field. - First paragraph introduce this but the later passage shifts towards about X-ray and CT and how they both co-exisit.

(B) Without replacing x—ray techniques, the development of CT has widened the scope of imaging technology  - Correct, capture the essence of the passage, that although CT is developed over X-rays. Both are important in the imaging.

(C) Although CT has many virtues, it has some major drawbacks as well - Partially correct, but X-rays is more prominently discussed in the passage over CT.

(D) Imaging techniques have permitted physicians to diagnose many internal disorders without surgery. - Yes, but the passage is limited to only 2 imaging tehcniques and how they have widen the scope of imaging.

(E) The most important factor in assessing the value of imaging techniques is speed. - Incorrect, better imaging quality is more important than speed.

2. According to the passage, all of the following are true about conventional x—ray imaging EXCEPT that it

(A) was the first imaging technique invented  - The field of imaging technology began in 1895 with the discovery of x—rays, which first

(B) is the most popular of the imaging techniques - X—rays remain the most widely used imaging technique

(C) records virtually all transmitted radiation  - Incorrect, Refer to the line "Today fluorescent screen film combinations can register more than 60 percent of the radiation striking them."  more than 60% is not equal to 100%(all) .

(D) produces images rapidly - and the consequent high rate at which images can be repeate

(E) was developed after 1894 -began in 1895

3. It can be inferred from the passage that in conventional x—ray imaging one characteristic of the beam is that it 
(A) undergoes significant scattering on transmission through the body - Image cannot be produced if the beams are scattered, objective is to decrease the scattered rays.

(B) is accurately maintained at an extremely narrow width - This is the advantage of CT over X-rays.

(C) requires a great deal of energy to operate - The opeartion of the beam is not discussed.

(D) can be moved rapidly from one part of the body to another - The movement of rapidly moving one body organ is discussed and not movement from one part to another.

(E) is mostly absorbed by the tissue of the body -  Correct, Refer to the line " Today fluorescent screen film combinations can register more than 60 percent of the radiation striking them. "

4. It can be inferred from the passag that one purpose of the fluorescent screen in conventional x—ray imaging is to 
(A) monitor the amount of radiation the patient has received

(B) hold in place the light-sensitive film for the X—ray image

(C) allow the physician to judge immediately the quality of the X—ray image - The

(D) produce an image of the irradiated organ for the film
Yes, "he technique consists of irradiating the relevant part of the body with an x—ray source and allowing the x—rays that are transmitted to strike an x-ray-sensitive fluorescent screen, which then balkens a sheet of light—sensitive film, thereby producing a two—dimensional image of a three—dimensional structure."

(E) control the speed at which an image is produced -

5. According to the passage, CT imaging has been particularly useful for 
(A) imaging the lungs - Related to X-rays for high contrast body parts

(B) analyzing some cancers  - Refer to the line "For this reason, CT has proved invaluable for imaging the brain, for diagnosing hemorrhage and stroke, and for  evaluating certain kinds of cancers ."

(C) diagnosing bone injuries - Related to X-rays for high contrast body parts

(D) observing the muscles of the heart during contraction - Related to X-rays use for rapidly moving organs

(E) studying the motions of the stomach during digestion - Related to X-rays use for rapidly moving organs

6. The passage would most likely appear in a 
Passage is about how imaging has developed and the language written is simple and describe both X-rays and CT scan. It is likely written for a textbook.

(A) science magazine for nonspecialists - The data is written for people who are able to understand key scientific terms used in the passage.

(B) textbook on radiation physics - The passage discuss only imaging technology and not introduce radiation physics

(C) medical research journal  - The research is correct which shows how imaging techniques evolve from X-ray to CT.

(D) CT users' manual - CT is part of passage, X-rays are also mentioned.

(E) monograph on early twentieth—century medical technology - monograph is written by a specialist, the content in the passage is not exclusive.

7. It can be inferred from the passage that CT is extremely valuable for imaging the brain primarily because 
(A) tomograms of the brain give the best picture of the activities of the brain - We cannot certain that they give the best picture.

(B) the brain is composed of tissues whose contrast differences are not very great - There is white and gray matter in the brain which shows a clear contrast.

(C) only relatively slow imaging techniques can produce medically useful images of the brain - We cannot determine that there exist any other technology which can produce medically useful images. There may be other technologies which are not discussed in the passage.

(D) better images can be constructed out of profiles of the relatively small brain than out of profiles of larger areas of the body  - Refer to the line "These  images are more readily comprehended than conventional x—ray images  because confusion caused by superimposition is eliminated,"

(E) x—rays are unable to penetrate the skull sufficiently to obtrain a sharp picture of the brain- X-rays are able to peneterate, they just not able to provide clear images than CT.

8. Which of the following ways of obtaining information is most like CT imaging? 
(A) Learning about a house by looking in the front door - No the individual slices are being made to study and not just by looking.

(B) Studying an orange by peeling it - No part of the organ is removed.

(C) Characterizing a crystal by measuring the angle between two faces - This method is not being used.

(D) Studying a tree trunk by making slices through the trunk  - Correct, refer to the line "CT also requires that the body be viewed  as a series of many individual slices , but it has the unique attribute of being sensitive to extremely slight contrast differences in tissue — it can, for example, discriminate between white and gray matter in the brain. "

(E) Learning about a coconut by drilling a hole in it- The organ is not exposed in open in CT.

IMO BCEDBCDD

Sajjad1994 · Answer

Official Explanation

1. Which of the following best summarizes the author's main point?

Explanation

(A)  While the passage mentions the discovery of x-rays in 1895 and their importance in the field of imaging technology, the main point goes beyond the introduction of x-ray techniques. The passage discusses the continued development and advancements in imaging technology, particularly the introduction of computed tomography (CT).

(B)   This is the most accurate summary. The passage acknowledges the significance of x-ray techniques but emphasizes the development of computed tomography (CT) as a refinement and expansion of imaging technology.

(C)  The passage does mention some drawbacks of CT, such as being more time-consuming than imaging on film, but it doesn't emphasize them as major drawbacks. The overall tone is more positive about the contributions of CT.

(D)  While the passage does highlight the diagnostic capabilities of imaging techniques, it doesn't specifically focus on the avoidance of surgery as the primary point. It emphasizes the evolution and advantages of different imaging methods.

(E)  The passage does mention the advantage of speed in film techniques, but it doesn't claim that speed is the most important factor in assessing the value of imaging techniques. The passage discusses various factors contributing to the usefulness of different techniques.

Answer: B

Sajjad1994 · Answer

Official Explanation

2. According to the passage, all of the following are true about conventional x—ray imaging EXCEPT that it

Explanation

(A)  The passage mentions that the field of imaging technology began in 1895 with the discovery of x-rays. Therefore, conventional x-ray imaging was one of the earliest imaging techniques invented. This statement is true.

(B)  The passage states that x-rays remain the most widely used imaging technique. This indicates that x-rays are popular and widely utilized. This statement is true.

(C)   The passage mentions that fluorescent screen film combinations used in x-ray techniques can register more than 60 percent of the radiation striking them. This indicates that not all transmitted radiation is recorded, making option (C) incorrect. This is the answer.

(D)  The passage mentions the great advantage of film techniques (including x-ray) is the relatively short time it takes to acquire a complete image. This indicates that x-ray imaging produces images rapidly. This statement is true.

(E)  The passage does not provide information on the specific year when conventional x-ray imaging was developed. However, since the field of imaging technology began in 1895 with the discovery of x-rays, it is reasonable to infer that conventional x-ray imaging was developed after 1894. Therefore, this statement is likely true.

Answer: C

Sajjad1994 · Answer

Official Explanation

3. It can be inferred from the passage that in conventional x—ray imaging one characteristic of the beam is that it

Explanation

(A)   The passage does mention that in CT imaging, the narrowness of the beam markedly decreases the registration of scattered rays. It is reasonable to infer that some scattering may occur as x-rays pass through the body. Therefore,  option (A)  is a plausible characteristic of the x-ray beam in conventional imaging.

(B)  The passage doesn't provide information about the width of the x-ray beam in conventional x-ray imaging.

(C)  The passage doesn't provide information about the energy requirements of conventional x-ray imaging.

(D)  The passage mentions the advantage of film techniques, including x-ray, is the relatively short time it takes to acquire a complete image. However, this doesn't necessarily imply that the x-ray beam itself can be moved rapidly from one part of the body to another.

(E)  This cannot be inferred.

Sajjad1994 · Answer

Official Explanation

4. It can be inferred from the passag that one purpose of the fluorescent screen in conventional x—ray imaging is to

Explanation

The passage describes the process of conventional x-ray imaging, where the relevant part of the body is irradiated with x-rays. The x-rays that are transmitted through the body strike an x-ray-sensitive fluorescent screen. This screen, in turn, produces a two-dimensional image of the three-dimensional structure of the irradiated organ. The image on the fluorescent screen is then captured by a sheet of light-sensitive film, creating a record of the x-ray image.

Therefore, the fluorescent screen plays a crucial role in producing the visual image of the irradiated organ for the subsequent creation of the x-ray image on the film.  Option (D)  accurately captures this purpose.

Answer: D

Sajjad1994 · Answer

Official Explanation

5. According to the passage, CT imaging has been particularly useful for

Explanation

The passage mentions that CT imaging has the unique attribute of being sensitive to extremely slight contrast differences in tissue. It specifically states that CT has proved invaluable for imaging the brain, diagnosing hemorrhage and stroke, and evaluating certain kinds of cancers. Therefore,  option (B), "analyzing some cancers,"  accurately reflects the information provided in the passage.

Answer: B

Sajjad1994 · Answer

Official Explanation

6. The passage would most likely appear in a

Explanation

The passage provides a general overview of the field of imaging technology, starting from its historical roots in the discovery of x-rays to recent advances, particularly in computed tomography (CT). It does not delve deeply into technical details or specialized knowledge, making it accessible to a general audience. Therefore, the passage would most likely appear in a science magazine for nonspecialists.

Answer: A

Sajjad1994 · Answer

Official Explanation

7. It can be inferred from the passage that CT is extremely valuable for imaging the brain primarily because

Explanation

(A)  The passage doesn't provide information about capturing the activities of the brain; it focuses on imaging structures.

(B)   This is the correct inference based on the passage. The passage mentions that CT is valuable for imaging the brain because it can discriminate between white and gray matter, suggesting that the contrast differences in brain tissues are not very great.

(C)  The passage mentions that CT imaging is more time-consuming than imaging on film, but it doesn't suggest that only slow imaging techniques are useful for the brain.

(D)  The passage doesn't make a direct comparison between the size of the brain and other body parts in the context of image construction.

(E)  The passage doesn't explicitly state this.

Answer: B

Sajjad1994 · Answer

Official Explanation

8. Which of the following ways of obtaining information is most like CT imaging?

Explanation

In CT imaging, the technique involves obtaining a series of thin slices (profiles) through the body and combining them to create a tomogram, providing a detailed view of the internal structure. Similarly, in  option (D) , studying a tree trunk by making slices through the trunk is analogous to the process of CT imaging. Slicing through the tree trunk allows for a comprehensive examination of the internal structure of the trunk, just as CT imaging creates a detailed view of the internal structures of the body.

(A)  This option doesn't involve the systematic and detailed slicing or sectioning akin to CT imaging.

(B)  Peeling an orange reveals its internal structure, but it doesn't involve creating a series of slices to obtain a comprehensive view like CT imaging.

(C)  This option involves measuring angles and characterizing a crystal, which is a different method compared to the sequential slicing in CT imaging.

(E)  Drilling a hole in a coconut might provide some information about its internal content, but it doesn't involve the systematic and sequential slicing characteristic of CT imaging.

Answer: D

agrasan · Answer

Hi experts  KarishmaB   GMATNinja   DmitryFarber

6. The passage would most likely appear in a

(E) monograph on early twentieth-century medical technology

Why option E is wrong here, I am unable to draw a proper reasoning for that. Could you please help me? 
My initial thinking was: the passage does cover a brief background on early 20th medical technology (both x-ray and CT), hence, it can appear in a monograph (long-article or short book).

KarishmaB · Answer

The passage starts with the end of 19th century timeline and moves on to recent decades and today i.e. the 21st century. 20th century is not mentioned.

catcun · Answer

@egmat in question 8, although D seems like an obvious choice, doesn???t it imply physically cutting the trunk? How is that correct?

guddo · Answer

8. Which of the following ways of obtaining information is most like CT imaging?

The passage explains that CT imaging builds understanding by scanning  many thin slices  of an object and combining them, instead of producing one flat, compressed image. This slice-by-slice approach removes overlap and reveals fine internal differences.

(A) Learning about a house by looking in the front door

This does not match. Looking through a door gives a single, partial view, similar to a flat image, not layered internal analysis.

(B) Studying an orange by peeling it

I do not think this fits. Peeling an orange removes layers entirely, but CT does not remove material; it scans successive internal slices while keeping the object intact.

(C) Characterizing a crystal by measuring the angle between two faces

This is unrelated. Measuring angles between crystal faces gives surface information, not internal structure.

(D) Studying a tree trunk by making slices through the trunk

D. This aligns best. Studying a tree trunk by making slices directly mirrors CT imaging: understanding internal structure by examining  thin cross-sections one at a time .

(E) Learning about a coconut by drilling a hole in it

This does not work. Drilling a hole gives very limited, localized information, not a systematic slice-by-slice view.

Answer: (D)

guddo · Answer

The key is  what the analogy is about , not the physical act.

CT imaging does  not  mean literally cutting the body, but it  conceptually  treats the body as a series of thin slices to understand internal structure. Option D matches that idea exactly: learning by examining  cross-sections , one slice at a time.

The question is about  method of obtaining information , not invasiveness. So even though slicing a trunk is physical, it mirrors the  slice-by-slice analysis  CT uses. That’s why D is correct despite the wording.

GG27 · Answer

Hi  GMATNinja , In Q8, I chose option C. I eliminated B, D, and E. These options suggest peeling, making slices, or drilling a hole, which, in my opinion, can not be compared to CT because CT is a non-invasive procedure. Between A and C - I found C stronger than A, thats why I chose A. Any insights on where I went wrong in my understanding?

8. Which of the following ways of obtaining information is most like CT imaging?

(A) Learning about a house by looking in the front door
(B) Studying an orange by peeling it
(C) Characterizing a crystal by measuring the angle between two faces
(D) Studying a tree trunk by making slices through the trunk
(E) Learning about a coconut by drilling a hole in it

The field of imaging technology began in 1895 with the discovery of

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The field of imaging technology began in 1895 with the discovery of

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