About twice every century, one of the massive stars in our galaxy blow

Question

About twice every century, one of the massive stars in our galaxy blows itself apart in a supernova explosion that sends massive quantities of radiation and matter into space and generates shock waves that sweep through the arms of the galaxy. The shock waves heat the interstellar gas, evaporate small clouds, and compress larger ones to the point at which they collapse under their own gravity to form new stars. The general picture that has been developed for the supernova explosion and its aftermath goes something like this. Throughout its evolution, a star is much like a leaky balloon. It keeps its equilibrium figure through a balance of internal pressure against the tendency to collapse under its own weight. The pressure is generated by nuclear reactions in the core of the star which must continually supply energy to balance the energy that leaks out in the form of radiation. Eventually the nuclear fuel is exhausted, and the pressure drops in the core. With nothing to hold it up, the matter in the center of the star collapses inward, creating higher and higher densities and temperatures, until the nuclei and electrons are fused into a super-dense lump of matter known as a neutron star.

As the overlying layers rain down on the surface of the neutron star, the temperature rises, until with a blinding flash of radiation, the collapse is reversed. A thermonuclear shock wave runs through the now expanding stellar envelope, fusing lighter elements into heavier ones and producing a brilliant visual outburst that can be as intense as the light of 10 billion suns. The shell of matter thrown off by the explosion plows through the surrounding gas, producing an expanding bubble of hot gas, with gas temperatures in the millions of degrees. This gas will emit most of its energy at X-ray wavelengths, so it is not surprising that X-ray observatories have provided some of the most useful insights into the nature of the supernova phenomenon. More than twenty supernova remnants have now been detected in X-ray studies.

Recent discoveries of  meteorites  with anomalous concentrations of certain isotopes indicate that a supernova might have precipitated the birth of our solar system more than four and a half billion years ago. Although the cloud that collapsed to form the Sun and the planets was composed primarily of hydrogen and helium, it also contained carbon, nitrogen, and oxygen, elements essential for life as we know it. Elements heavier than helium are manufactured deep in the interior of stars and would, for the most part, remain there if it were not for the cataclysmic supernova explosions that blow giant stars apart. Additionally, supernovas produce clouds of high-energy particles called cosmic rays. These high-energy particles continually bombard the Earth and are responsible for many of the genetic mutations that are the driving force of the evolution of species.    1  
 1. Which of the following titles best describes the content of the passage?

(A) The Origins and Effects of Supernovas
(B) The Life and Death of Stars
(C) The Origins and Evolution of Life on Earth
(D) The Aftermath of a Supernova
(E) Violent Change in the Universe

2  
 2. According to the passage, we can expect a supernova to occur in our galaxy

(A) about twice each year
(B) hundreds of times each century
(C) about once every fifty years
(D) about once every other century
(E) about once every four to five billion years

3  
 3. According to the passage all of the following are true of supernovas EXCEPT that they

(A) are extremely bright
(B) are an explosion of some sort
(C) emit large quantities of X-rays
(D) result in the destruction of a neutron star
(E) are caused by the collision of large galaxies

4  
 4. The author employs which of the following to develop the first paragraph?

(A) Analogy
(B) Deduction
(C) Generalization
(D) Example
(E) Refutation

5  
 5. It can be inferred from the passage that the meteorites ( Highlighted ) mentioned by the author

(A) contain dangerous concentrations of radioactive materials
(B) give off large quantities of X-rays
(C) include material not created in the normal development of our solar system
(D) are larger than the meteors normally found in a solar system like ours
(E) contain pieces of a supernova that occurred several billion years ago

6  
 6. The author implies that

(A) it is sometimes easier to detect supernovas by observation of the X-ray spectrum than by observation of visible wavelengths of light
(B) life on Earth is endangered by its constant exposure to radiation forces that are released by a supernova
(C) recently discovered meteorites indicate that the Earth and other planets of our solar system survived the explosion of a supernova several billion years ago
(D) lighter elements are formed from heavier elements during a supernova as the heavier elements are torn apart
(E) the core of a neutron star is composed largely of heavier elements such as carbon, nitrogen, and oxygen

7  
 7. According to the passage what is the first event in the sequence that leads to the occurrence of a supernova?

(A) An ordinary star begins to emit tremendous quantities of X-rays.
(B) A neutron star is enveloped by a superheated cloud of gas.
(C) An imbalance between light and heavy elements causes an ordinary star to collapse.
(D) A cloud of interstellar gas rich in carbon, nitrogen, and oxygen, collapses to form a neutron star.
(E) An ordinary star exhausts its supply of nuclear fuel and begins to collapse.

8  
 8. According to the passage a neutron star is

(A) a gaseous cloud containing heavy elements
(B) an intermediate stage between an ordinary star and a supernova
(C) the residue that is left by a supernova
(D) the core of an ordinary star that houses the thermonuclear reactions
(E) one of billions of meteors that are scattered across the galaxy by a supernova

9  
 9. The author is primarily concerned with

(A) speculating about the origins of our solar system
(B) presenting evidence proving the existence of supernovas
(C) discussing the nuclear reaction that occurs in the core of a star
(D) describing the sequence of scientific events
(E) disproving a theory about the causes of supernovas

kitipriyanka · Answer

1. Which of the following titles best describes the content of the passage?

(A) The Origins and Effects of Supernovas
(B) The Life and Death of Stars
(C) The Origins and Evolution of Life on Earth
(D) The Aftermath of a Supernova
(E) Violent Change in the Universe

1st para - how is Supernova originated

2nd para - Effects of Supernove

3rd para - Effects of Supernova.

This RC is all about Supernova. There are two options A or D. However D is a trap  supernova explosion and its aftermath  goes something like this.] Answer is A.

2. According to the passage, we can expect a supernova to occur in our galaxy

(A) about twice each year
(B) hundreds of times each century
(C) about once every fifty years
(D) about once every other century
(E) about once every four to five billion years

About twice every century , one of the massive stars in our galaxy blows itself apart in a supernova explosion   Answer is C.

3. According to the passage all of the following are true of supernovas EXCEPT that they

(A) are extremely bright  producing a  brilliant visual outburst that can be as intense  as the light of 10 billion suns 
(B) are an explosion of some sort   supernova explosion ] 
(C) emit large quantities of X-rays  More than twenty  supernova remnants have now been detected in X-ray studies . 
(D) result in the destruction of a neutron star  As the overlying layers rain down on the  surface of the neutron star , the temperature rises, until with a blinding flash of radiation, the collapse is reversed.  A thermonuclear shock  wave runs through the now expanding stellar envelope 
(E) are caused by the collision of large galaxies

Therefore, Answer is E

4. The author employs which of the following to develop the first paragraph?

(A) Analogy 
(B) Deduction
(C) Generalization
(D) Example
(E) Refutation

Author tries to create an analogy by explaining how supernova explosion occurs in Stars. Hence Answer is A

5. It can be inferred from the passage that the meteorites mentioned by the author at line 39

(A) contain dangerous concentrations of radioactive materials
(B) give off large quantities of X-rays
(C) include material not created in the normal development of our solar system
(D) are larger than the meteors normally found in a solar system like ours
(E) contain pieces of a supernova that occurred several billion years ago

meteorites with anomalous concentrations of certain isotopes indicate that a  supernova might have precipitated the birth of our solar system  more than four and a half billion years ago. Although the cloud that collapsed to form the Sun and the planets was composed primarily of hydrogen and helium,  it also contained carbon, nitrogen, and oxygen, elements essential for life  as we know it.

Answer is C. Material here refers to "arbon, nitrogen, and oxygen"

6. The author implies that

(A) it is sometimes easier to detect supernovas by observation of the X-ray spectrum than by observation of visible wavelengths of light
(B) life on Earth is endangered by its constant exposure to radiation forces that are released by a supernova
(C) recently discovered meteorites indicate that the Earth and other planets of our solar system survived the explosion of a supernova several billion years ago
(D) lighter elements are formed from heavier elements during a supernova as the heavier elements are torn apart
(E) the core of a neutron star is composed largely of heavier elements such as carbon, nitrogen, and oxygen

This gas will emit most of its energy at  X-ray wavelengths , so it is  not surprising that X-ray observatories have provided some of the most useful insights into the nature of the supernova phenomenon.

Therefore, Answer is A

7. According to the passage what is the first event in the sequence that leads to the occurrence of a supernova?

(A) An ordinary star begins to emit tremendous quantities of X-rays.
(B) A neutron star is enveloped by a superheated cloud of gas.
(C) An imbalance between light and heavy elements causes an ordinary star to collapse.
(D) A cloud of interstellar gas rich in carbon, nitrogen, and oxygen, collapses to form a neutron star.
(E) An ordinary star exhausts its supply of nuclear fuel and begins to collapse.

Eventually  the nuclear fuel is exhausted , and the pressure drops in the core. With nothing to hold it up, the matter in the center of the  star collapses  inward

Therefore,Answer is E

8. According to the passage a neutron star is

(A) a gaseous cloud containing heavy elements
(B) an intermediate stage between an ordinary star and a supernova
(C) the residue that is left by a supernova
(D) the core of an ordinary star that houses the thermonuclear reactions
(E) one of billions of meteors that are scattered across the galaxy by a supernova

1st and 2nd para explains ordinary star -> neutron star -> supernova
Hence Answer is B

9. The author is primarily concerned with

(A) speculating about the origins of our solar system
(B) presenting evidence proving the existence of supernovas
(C) discussing the nuclear reaction that occurs in the core of a star
(D) describing the sequence of scientific events
(E) disproving a theory about the causes of supernovas

1st para - Scientific events involved in the origination of supernova.

2nd para - Its effects on neutron star, gases produced and X-rays

3rd para - Effect on solar system, cosmic rays

Hence, answer is D

Skywalker18 · Answer

All correct in 12 mins 30 seconds, including 4 mins 40 seconds to read

Para 1- Supernova --how it occurs? , aftermath , neutron star formation
Para 2- continuation, usage of X-rays
Para 3- Supernova precipitated our solar system, cosmic rays - mutation

1. Which of the following titles best describes the content of the passage?
(A) The Origins and Effects of Supernovas - Correct

2. According to the passage, we can expect a supernova to occur in our galaxy
(C) about once every fifty years

About twice every century, one of the massive stars in our galaxy blows itself apart in a supernova explosion that sends massive quantities of radiation and matter into space and generates shock waves that sweep through the arms of the galaxy

3. According to the passage all of the following are true of supernovas EXCEPT that they
(A) are extremely bright - incorrect, fusing lighter elements into heavier ones and producing a brilliant visual outburst that can be as intense as the light of 10 billion suns
(B) are an explosion of some sort- incorrect , in a supernova explosion that sends massive quantities of radiation and matter into space and generates shock waves
(C) emit large quantities of X-rays - incorrect, This gas will emit most of its energy at X-ray wavelengths
(D) result in the destruction of a neutron star- incorrect, As the overlying layers rain down on the surface of the neutron star, the temperature rises, until with a blinding flash of radiation, the collapse is reversed
(E) are caused by the collision of large galaxies- Correct

4. The author employs which of the following to develop the first paragraph?
(A) Analogy

The general picture that has been developed for the supernova explosion and its aftermath goes something like this. Throughout its evolution, a star is much like a leaky balloon.

5. It can be inferred from the passage that the meteorites (Highlighted) mentioned by the author
(C) include material not created in the normal development of our solar system

Recent discoveries of meteorites with anomalous concentrations of certain isotopes indicate that a supernova might have  precipitated the birth of our solar system  more than four and a half billion years ago.

6. The author implies that
(A) it is sometimes easier to detect supernovas by observation of the X-ray spectrum than by observation of visible wavelengths of light

This gas will emit most of its energy at X-ray wavelengths, so it is not surprising that X-ray observatories have provided some of the most useful insights into the nature of the supernova phenomenon. More than twenty supernova remnants have now been detected in X-ray studies.

7. According to the passage what is the first event in the sequence that leads to the occurrence of a supernova?
(E) An ordinary star exhausts its supply of nuclear fuel and begins to collapse.

The pressure is generated by nuclear reactions in the core of the star which must continually supply energy to balance the energy that leaks out in the form of radiation. Eventually the nuclear fuel is exhausted, and the pressure drops in the core. With nothing to hold it up, the matter in the center of the star collapses inward, creating higher and higher densities and temperatures, until the nuclei and electrons are fused into a super-dense lump of matter known as a neutron star.

8. According to the passage a neutron star is
(B) an intermediate stage between an ordinary star and a supernova- Correct

9. The author is primarily concerned with

(A) speculating about the origins of our solar system- too narrow scope- talked in last para
(B) presenting evidence proving the existence of supernovas- incorrect
(C) discussing the nuclear reaction that occurs in the core of a star - incorrect-- too much of detail
(D) describing the sequence of scientific events- correct
(E) disproving a theory about the causes of supernovas- incorrect, no theory is disproven

huongguyen · Answer

1. Which of the following titles best describes the content of the passage?

(A) The Origins and Effects of Supernovas → make sense 
(B) The Life and Death of Stars → discuss only supernovas. 
(C) The Origins and Evolution of Life on Earth → minor mention at the 3rd paragraph
(D) The Aftermath of a Supernova → minor mention at the 2nd, 3rd paragraph
(E)  Violent Change  in the Universe

==> A

2. According to the passage, we can expect a supernova to occur in our galaxy
 Scope line: About twice every century, one of the massive stars in our galaxy blows itself apart in a supernova explosion 
 (A) about twice  each year  
(B)  hundreds of times  each century 
(C) about once every fifty years  → yes, do simple maths.  
(D) about  once every other century 
(E) about once  every four to five billion years

3. According to the passage all of the following are  true of supernovas   EXCEPT  that they

(A) are extremely bright →  “producing a brilliant visual outburst” 
(B) are an explosion of some sort --> yes, throughout of the passage we'll get this. 
(C) emit large quantities of X-rays  → “This gas will emit most of its energy at X-ray wavelengths” 
(D) result in the destruction of a neutron star →  “ until the nuclei and electrons are fused into a super-dense lump of matter known as a neutron star. 
As the overlying layers rain down on the surface of the neutron star, the temperature rises, until with a blinding flash of radiation, the collapse is reversed. 
(E) are caused by the  collision  of large galaxies → not mentioned

4. The author employs which of the following to develop the first paragraph?

(A) Analogy  → “Throughout its evolution, a star is much  like  a leaky balloon.”  
 (B) Deduction 
(C) Generalization
(D) Example
(E) Refutation

huongguyen · Answer

5. It can be inferred from the passage that the meteorites (Highlighted) mentioned by the author
 Scope line: “Recent discoveries of meteorites with anomalous concentrations of certain isotopes indicate that a supernova might have precipitated the birth of our solar system more than four and a half billion years ago.”
 
→ Mainpoint: anomalous con. + sinh ra our solar system 
(A) contain dangerous concentrations of radioactive materials  → it just shows that it has anolamous concentrations, No comment on this concentration at all

(B) give off large quantities of X-rays  → not mentioned 
(C) include material not created in the normal development of our solar system → not normal = anomalous  --> Hold.  
(D) are larger than the meteors normally found in a solar system like ours  → no comparisons.  
(E) contain pieces of a supernova that occurred several billion years ago → Out of scope

6. The author implies that

(A) it is sometimes easier to detect supernovas by observation of the X-ray spectrum than by observation of visible wavelengths of light →  Scope line: “This gas will emit most of its energy at X-ray wavelengths, so it is not surprising that X-ray observatories have provided some of the most useful insights into the nature of the supernova phenomenon. More than twenty supernova remnants have now been detected in X-ray studies.”

(B) life on Earth is endangered by its constant exposure to radiation forces that are released by a supernova  → no comments about dangers or such things  
(C) recently discovered meteorites indicate that the Earth and other planets of our solar system survived the explosion of a supernova several billion years ago  → not mentioned 
(D) lighter elements are formed from heavier elements during a supernova as the heavier elements are torn apart  → only list elements, the passage doesn't say which elements form which elements.

(E) the core of a neutron star is composed largely of  heavier elements  such as carbon, nitrogen, and oxygen

7. According to the passage, what is the first event in the sequence that leads to the occurrence of a supernova?
 The general picture that has been developed for the supernova explosion and its aftermath goes something like this.
Eventually the nuclear fuel is exhausted, and the pressure drops in the core. With nothing to hold it up, the matter in the center of the star collapses inward, creating higher and higher densities and temperatures, until the nuclei and electrons are fused into a super-dense lump of matter known as a neutron star. 
(A) An ordinary star begins to emit tremendous quantities of X-rays. → OOS
(B) A neutron star is enveloped by a superheated cloud of gas.--> OOS
(C) An imbalance between light and heavy elements causes an ordinary star to collapse. → wrong info
(D) A cloud of interstellar gas rich in carbon, nitrogen, and oxygen, collapses to form a neutron star. → OOS 
(E) An ordinary star exhausts its supply of nuclear fuel and begins to collapse.

8. According to the passage a neutron star is
 Scope: “ With nothing to hold it up, the matter in the center of the star collapses inward, creating higher and higher densities and temperatures, until the nuclei and electrons are fused into a super-dense lump of matter known as a neutron star.”
1st and 2nd para explains ordinary star -> neutron star -> supernova
 
(A) a gaseous cloud containing  heavy elements 
(B) an intermediate stage between an ordinary star and a supernova
(C) the residue that is  left by a supernova 
(D) the core of an ordinary star that houses the  thermonuclear  reactions 
(E)  one of billions of meteors  that are scattered across the galaxy by a supernova

9. The author is primarily concerned with

(A)  speculating  about the origins of our solar system
(B) presenting evidence proving the  existence of supernovas
 (C) discussing the  nuclear reaction  that occurs in the core of a star
(D) describing the  sequence  of scientific events
(E)  disproving a theory  about the causes of supernovas

TheAdmissionHub · Answer

Passage Analysis 
 Paragraph 1 – What the author does: 
The author  introduces the phenomenon of supernovas  and explains the first stages of a star’s life cycle. He describes how a massive star remains stable through a balance between internal pressure and gravity, and how the exhaustion of nuclear fuel causes the star’s core to collapse and form a neutron star.
 Short summary: 
A massive star runs out of nuclear fuel, collapses under its own gravity, and forms a neutron star, beginning the process that leads to a supernova.

Paragraph 2 – What the author does: 
The author  describes the explosion of a supernova and its immediate effects . He explains how the collapse is reversed, how the star releases enormous amounts of energy, and how the explosion creates expanding clouds of hot gas that can be studied through X-rays.
 Short summary: 
A supernova explosion releases huge amounts of energy, creates heavy elements, and produces hot gas that emits X-rays.

Paragraph 3 – What the author does: 
The author  explains the importance of supernovas for the formation of the solar system and life on Earth . He discusses how supernovas create heavy elements, may have contributed to the birth of our solar system, and produce cosmic rays that influence evolution.
 Short summary: 
Supernovas create essential elements, may have helped form our solar system, and affect life through cosmic rays.

1. Which of the following titles best describes the content of the passage?

(A)  The Origins and Effects of Supernovas
 CORRECT:  The passage explains how supernovas originate, how massive stars explode, and what effects they have, including the creation of heavy elements and cosmic rays.
  (B)  The Life and Death of Stars 
 WRONG:  This title is too general because the passage does not describe the entire life cycle of stars; it focuses mainly on the supernova phenomenon.
 (C)  The Origins and Evolution of Life on Earth
 WRONG:  The passage only briefly mentions life on Earth as a consequence of cosmic rays and elements created by supernovas.
 (D)  The Aftermath of a Supernova
 WRONG : The passage does discuss the effects after an explosion, but it also explains the events that happen before and during a supernova.
 (E)  Violent Change in the Universe
 WRONG : This title is too broad and does not clearly identify the main subject of the passage.

2. According to the passage, we can expect a supernova to occur in our galaxy 
 (A)  about twice each year
 WRONG : The passage states that supernovas occur about twice every century, not twice every year.
 (B)  hundreds of times each century
 WRONG:  The number is much smaller; the author mentions only about two supernovas per century.
 (C)  about once every fifty years
 CORRECT:  The passage says “about twice every century.” Since a century is 100 years, this means approximately one supernova every 50 years.
 (D)  about once every other century
 WRONG:  This would mean about once every 200 years, which is less frequent than what the passage states.
 (E)  about once every four to five billion years
 WRONG:  This refers to the age of the solar system, not the frequency of supernova explosions.

3. According to the passage all of the following are true of supernovas EXCEPT that they

(A)  are extremely bright
 WRONG:  The passage states that a supernova can produce an explosion as bright as the light of 10 billion suns, so this statement is true.
 (B)  are an explosion of some sort
 WRONG:  The passage repeatedly describes supernovas as explosions involving massive stars.
 (C)  emit large quantities of X-rays
 WRONG:  The author explains that supernova remnants emit much of their energy at X-ray wavelengths.
 (D)  result in the destruction of a neutron star
 WRONG:  Although the neutron star is involved in the collapse process, the passage does not clearly describe its destruction. However, this option is not the best EXCEPT answer.
 (E)  are caused by the collision of large galaxies
 CORRECT:  The passage explains that supernovas are caused by the collapse and explosion of massive stars, not by galaxy collisions.

4. The author employs which of the following to develop the first paragraph?

(A)  Analogy
 CORRECT:  The author compares a star to “a leaky balloon” to explain the balance between internal pressure and gravity in a simple way.
 (B)  Deduction
 WRONG:  The author is not reaching a conclusion from a general principle; he is explaining a scientific process.
 (C)  Generalization
 WRONG:  The paragraph does not simply make a broad statement; it explains a specific physical process.
(D) Example
 WRONG : The author does not use a particular case as an example.
 (E)  Refutation
 WRONG:  The author does not reject or disprove another theory.

5. It can be inferred from the passage that the meteorites mentioned by the author

(A)  contain dangerous concentrations of radioactive materials
WRONG: The passage mentions unusual isotopes but does not say they are dangerous or radioactive in harmful amounts.
 (B)  give off large quantities of X-rays
 WRONG:  X-rays are associated with supernova remnants, not with meteorites.
 (C)  include material not created in the normal development of our solar system
 CORRECT:  The unusual isotopes found in meteorites suggest that some materials came from a supernova before the formation of our solar system.
 (D)  are larger than the meteors normally found in a solar system like ours
 WRONG:  The passage gives no information about the size of these meteorites.
 (E)  contain pieces of a supernova that occurred several billion years ago
 WRONG:  The meteorites contain elements produced by supernovas, but they are not actual pieces of a supernova.

6. The author implies that

(A ) it is sometimes easier to detect supernovas by observation of the X-ray spectrum than by observation of visible wavelengths of light
 CORRECT:  The author explains that supernova remnants emit most of their energy as X-rays and that X-ray observatories provide important information about them.
 (B)  life on Earth is endangered by its constant exposure to radiation forces that are released by a supernova
 WRONG:  The passage mentions that cosmic rays can cause mutations, but it does not say that supernovas constantly endanger life on Earth.
 (C)  recently discovered meteorites indicate that the Earth and other planets survived the explosion of a supernova several billion years ago
 WRONG:  The meteorites suggest that a supernova may have helped trigger the formation of the solar system, not that Earth survived one.
 (D)  lighter elements are formed from heavier elements during a supernova as the heavier elements are torn apart
 WRONG:  The passage says the opposite: lighter elements are fused into heavier ones during the explosion.
 (E)  the core of a neutron star is composed largely of heavier elements such as carbon, nitrogen, and oxygen
 WRONG:  Carbon, nitrogen, and oxygen are discussed as elements in the solar system, not as the main components of neutron stars.

7. According to the passage what is the first event in the sequence that leads to the occurrence of a supernova?

(A)  An ordinary star begins to emit tremendous quantities of X-rays
 WRONG : X-rays are produced after the explosion, not at the beginning of the process.
 (B)  A neutron star is enveloped by a superheated cloud of gas
 WRONG:  This happens after the collapse and explosion, not before.
 (C)  An imbalance between light and heavy elements causes an ordinary star to collapse
 WRONG:  The collapse occurs because the star runs out of nuclear fuel and loses internal pressure.
 (D)  A cloud of interstellar gas rich in carbon, nitrogen, and oxygen collapses to form a neutron star
 WRONG:  This describes the formation of stars and planets, not the beginning of a supernova.
 (E)  An ordinary star exhausts its supply of nuclear fuel and begins to collapse
 CORRECT : The first event is the exhaustion of nuclear fuel, which causes the internal pressure to decrease and the core to collapse.

8. According to the passage a neutron star is

(A)  a gaseous cloud containing heavy elements
 WRONG:  A neutron star is not a cloud of gas; it is an extremely dense object made of compressed matter.
 (B)  an intermediate stage between an ordinary star and a supernova
 CORRECT : The neutron star forms after the collapse of the star’s core and before the supernova explosion.
 (C)  the residue that is left by a supernova
 WRONG:  Some neutron stars can remain after supernovas, but the passage describes the neutron star as forming before the explosion.
 (D)  the core of an ordinary star that houses the thermonuclear reactions
 WRONG:  A normal star’s core produces energy through nuclear reactions, but it is not a neutron star.
 (E)  one of billions of meteors that are scattered across the galaxy by a supernova
 WRONG : A neutron star is not a meteor and is unrelated to scattered meteors.

9. The author is primarily concerned with

(A)  speculating about the origins of our solar system
 WRONG:  The origin of the solar system is only one consequence mentioned at the end of the passage.
 (B)  presenting evidence proving the existence of supernovas
 WRONG:  The author assumes supernovas exist and focuses on explaining their process.
 (C)  discussing the nuclear reaction that occurs in the core of a star
WRONG: Nuclear reactions are only one part of the explanation, not the main purpose.
 (D)  describing the sequence of scientific events
 CORRECT:  The passage mainly describes the chain of events leading from a massive star’s collapse to a supernova and its effects.
 (E)  disproving a theory about the causes of supernovas
 WRONG:  The author does not present or reject any alternative theory.

About twice every century, one of the massive stars in our galaxy blow

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GMAT Reading Comprehension (RC) Questions

About twice every century, one of the massive stars in our galaxy blow

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