A CT scan, used to capture images inside the body, differs from an MRI

A CT scan, used to capture images inside the body, differs from an MRI, bounced radio waves off fat and water molecules in the body and then to a receiver in the machine that creates an image.

A. bounced radio waves off fat and water molecules in the body and then to a receiver in
B. bouncing radio waves off fat and water molecules in the body to a receiver of
C. radio waves being bounced off fat and water molecules in the body to a receiver in
D. which bounce radio waves off fat and water molecules in the body and then to a receiver within
E. which bounces radio waves off fat and water molecules in the body to a receiver in

Explanation:

A- modifier error (modified entity is ambiguous here)Incorrect

B- Correct.Verb-ing modifier correctly modifying the preceding action-i.e "How a CT scan differs from an MRI" giving a clear &logically intended meaning.

C-Usage of Being is wrong here.Incorrect

D-Which wrongly modifies the nearest noun MRI also Subject veb agreement error 'MRI'- singular subject & 'bounce'- plural verb.Incorrect

E- Which wrongly modifies the nearest noun MRI.Although grammatically sounds right but changes the intended meaning as underlines modifier should modify the action of preceding clause to give extra information about "How a CT scan differs from an MRI"

Hence B is the correct answer.

A CT scan, used to capture images inside the body, differs from an MRI, bounced radio waves off fat and water molecules in the body and then to a receiver in the machine that creates an image.

A. bounced radio waves off fat and water molecules in the body and then to a receiver in Incorrect

redundancy problem - 'and than' not required

B. bouncing radio waves off fat and water molecules in the body to a receiver of Correct

seems good

C. radio waves being bounced off fat and water molecules in the body to a receiver in Incorrect

modifier error, being used is wrong

D. which bounce radio waves off fat and water molecules in the body and then to a receiver within Incorrect

modifier error - which modifies MRI, within uses wrong

E. which bounces radio waves off fat and water molecules in the body to a receiver in Incorrect

modifier error - which modifies MRI

A CT scan, used to capture images inside the body, differs from an MRI, bounced radio waves off fat and water molecules in the body and then to a receiver in the machine that creates an image.

A. bounced radio waves off fat and water molecules in the body and then to a receiver in -- wrong parallelism (bounced ... and to a ... )
B. bouncing radio waves off fat and water molecules in the body to a receiver of -- CORRECT, participial modifier to describe the previous clause about CT scan
C. radio waves being bounced off fat and water molecules in the body to a receiver in -- usage of being is wrong here
D. which bounce radio waves off fat and water molecules in the body and then to a receiver within -- "which" modifies MRI, SVA issue as well
E. which bounces radio waves off fat and water molecules in the body to a receiver in -- "which" wrongly modifies MRI and changes meaning


The answer should be B

Akp880
How is it clear that the modifier should be modifying CT scan and not MRI?

Right. It is difficult to know 'which xxxx' modified CT or MRI. IMO, it makes more sense to modify MRI instead of CT.
SVO, V-ing here: bouncing xx really doesn't explain well how CT differs from MRI. I would prefer to use which xxx to modify MRI.

I don't know much about SCs, but purely from a grammatical point of view there is nothing wrong with E.

Also a "receiver in the machine" sounds much better than "receiver of the machine", although both are again grammatically correct. Receivers (electrical components) are usually inside the machine.

I think if the only distinguishing feature between B and E is its intended meaning, this is too subtle and unfair for the test-taker. (of course this is true in case I have missed a subtle 'other' problem in E)

A CT scan, used to capture images inside the body, differs from an MRI, bounced radio waves off fat and water molecules in the body and then to a receiver in the machine that creates an image.

B. bouncing radio waves off fat and water molecules in the body to a receiver of

E. which bounces radio waves off fat and water molecules in the body to a receiver in

1-First of all try to understand the context of original stem.Verb-ing modifiers after comma are basically used to convey extra information either about The Subject(or doer) or about the action performed.(You may ask questions such as -When,How,why etc)
Here the later part fits well in structure,Verb-ing modifier is modifying the action of preceding clause by convey extra information "How CT san differs from an MRI"

2- "Which" is a "non-essential modifier" used only when the added information after removal from modified part leaves no impact.Here the part of information is essential to structure.Also note that MRI itself can not bounce radio waves off .Logically speaking MRI is a process and IMO it would be better to use "in which" instead of "Which"

[quote="St123Kt"] refer this buddy.

A. bounced radio waves off fat and water molecules in the body and then to a receiver in

should be at least -ing format, makes no sense. eliminate

B. bouncing radio waves off fat and water molecules in the body to a receiver of

A CT scan, ... differs from an MRI, bouncing radio waves off the molecules ...
It reads as if the CT scan differs from MRI while bouncing off waves!! which makes no sense. we know that -ing modifying phrase takes the same tense as the original verb. plus, 'receiver of the machine' is awkward.

C. radio waves being bounced off fat and water molecules in the body to a receiver in

makes no sense when you put together the whole sentence because we expect active voice here, but the passive voice here leads to ambiguity about who bounces the radio waves! eliminate

D. which bounce radio waves off fat and water molecules in the body and then to a receiver within

either the phrase is modifying CT scan or MRI, there is a singular/plural problem. bounces is mandatory. eliminate

E. which bounces radio waves off fat and water molecules in the body to a receiver in

Despite many friends here, I see no problem with this phrase which correctly modifies MRI. I would say this is the correct option.



I would love to know the original explanation though if I am wrong.

A CT scan, used to capture images inside the body, differs from an MRI, bounced radio waves off fat and water molecules in the body and then to a receiver in the machine that creates an image.

Split 1: Meaning and other grammatical issues
Eliminate the filler and you'll see that this is the correct sentence - A CT scan, used to capture images inside the body, differs from an MRI, bounced radio waves off fat and water molecules in the body and then to a receiver in the machine that creates an image. So whatever follows MRI has to be somewhat parallel without botching up the meaning. You're essentially offering up further info about CT scans and MRIs.

A. bounced radio waves off fat and water molecules in the body and then to a receiver in
This isn't parallel with what comes after and then - we need the present tense since presumably the workings of the MRI have not changed.

B. bouncing radio waves off fat and water molecules in the body to a receiver of
The use of an -ing modifier isn't too bad here but the tense becomes odd. The meaning becomes ambiguous though. A receiver of the machine producing an image sounds strange - is this external or internal? Cannot say but I think it would be internal. Also it isn't parallel with the modifier of CT.

C. radio waves being bounced off fat and water molecules in the body to a receiver in
Use of being is incorrect.

Split 2: Clarity and modifiers
D. which bounce radio waves off fat and water molecules in the body and then to a receiver within
MRI is singular so using the plural here is wrong so eliminate.

E. which bounces radio waves off fat and water molecules in the body to a receiver in
This one doesn't have any major errors. Which is preceded by a comma and describes the object before it. Looks corrects - meaning conveyed.

Going against the grain here, let's see how it goes!

A CT scan, used to capture images inside the body, differs from an MRI, bounced radio waves off fat and water molecules in the body and then to a receiver in the machine that creates an image.

A. bounced radio waves off fat and water molecules in the body and then to a receiver in
Incorrect
Bounced seems to be used as an ed modifier modifying MRI, which does not make any sense.
And then to receiver does not seem to be parallel with anything

B. bouncing radio waves off fat and water molecules in the body to a receiver of
Correct
Bouncing radio waves modifies the preceding clause. Where CT scan is the subject , though it's a bit far

C. radio waves being bounced off fat and water molecules in the body to a receiver in

Incorrect
Usage of being does not seem right here. How is this connected to the earlier clause. It is not making any sense .

D. which bounce radio waves off fat and water molecules in the body and then to a receiver within
Incorrect
Which is referring to MRI, which does not seem right.
Grammar error is the use of plural verb bounce

E. which bounces radio waves off fat and water molecules in the body to a receiver in
Incorrect
Same which issue as in D
Receiver in does not seem right.
I think receiver has to be something that is not inside the same machine. Generally speaking.

I will go with B.

Posted from my mobile device

Official Explanation

A CT scan, used to capture images inside the body, differs from an MRI, bounced radio waves off fat and water molecules in the body and then to a receiver in the machine that creates an image.

A. bounced radio waves off fat and water molecules in the body and then to a receiver in
B. bouncing radio waves off fat and water molecules in the body to a receiver of
C. radio waves being bounced off fat and water molecules in the body to a receiver in
D. which bounce radio waves off fat and water molecules in the body and then to a receiver within
E. which bounces radio waves off fat and water molecules in the body to a receiver in

After a quick glance over the options, we have 2 main areas we can focus on:
1. Their beginnings (Modifiers & Meaning)
2. Their endings (Punctuation & Meaning)

Let’s start off with #1 on our list. We need to determine what the purpose of the underlined phrase is to the whole sentence:

A CT scan, used to capture images inside the body, differs from an MRI, bounced radio waves off fat and water molecules in the body and then to a receiver in the machine that creates an image.

It appears that this sentence is doing two things:
1. Contrasting two machines (CT scan vs. MRI) = in blue
2. After introducing each machine, it explains what they do = in orange

We need to make sure the underlined modifier is clearly explains what an MRI does, and eliminate any that don’t accomplish this:

A. bounced radio waves off fat and water molecules in the body and then to a receiver in
(an MRI isn’t made out of radio waves, so this doesn’t really make sense)

B. bouncing radio waves off fat and water molecules in the body to a receiver of
(this suggests that the MRI does the action itself, which is also not logical)

C. radio waves being bounced off fat and water molecules in the body to a receiver in
(again, an MRI isn’t made of radio waves, it’s a machine that creates and bounces them around)

D. which bounce radio waves off fat and water molecules in the body and then to a receiver within
(much better indication of what an MRI does, which works well with the description of the CT scan earlier)

E. which bounces radio waves off fat and water molecules in the body to a receiver in
(much better indication of what an MRI does, which works well with the description of the CT scan earlier)

We can eliminate options A, B, and C because they create problematic issues with modifiers and the overall intended meaning of the sentence. Now that we have it narrowed down to only 2 options, let’s take a closer look at both to see which is the better choice:

D. which bounce radio waves off fat and water molecules in the body and then to a receiver within
This is INCORRECT for a couple reasons. First, the plural verb “bounce” doesn’t match up with the singular “MRI.” Second, the ending phrase is too wordy – option E says the same thing with far fewer words.

E. which bounces radio waves off fat and water molecules in the body to a receiver in
This is CORRECT! The verb “bounces” matches up perfectly with “MRI,” and the sentence is written using clear and concise language.

There you have it – option E is our winner!

Don’t study for the GMAT. Train for it.

You were close, Varunsawhney8! Check out the official explanation in the comments to see how to tackle this one.

Also - make sure it's clear which option you think is correct - you labeled all of these as "incorrect choice." They can't all be wrong!

You were so close, HoneyLemon! The "which" modifier DOES refer to the MRI machine. The word "bouncing" is NOT the main verb here - the main verb is "differs," which I think is where so many people got tripped up. Check out the official explanation in the comments!

You were so close, Akp880! Check out the official explanation in the comments to see how to tackle this one!

You were close, winterschool! The "which" modifier in option E is correct - it is supposed to modify MRI. Check out the official explanation in the comments to see how to tackle this one!

You were so close, NiftyNiffler! Check out the official explanation to see how to tackle this one!

Great question, ah1028! The answer to that is that the modifier IS supposed to modify MRI, not CT scan! Option E does this the best, which is why it's the correct choice!

Check out the official explanation in the comments to see how you should tackle questions like this!