In large doses, analgesics that work in the brain as antagonists to ce

Question

In large doses, analgesics that work in the brain as antagonists to certain chemicals have caused psychological disturbances in patients,  which may limit their potential to relieve  severe pain.

(A) which may limit their potential to relieve

(B) which may limit their potential for relieving

(C) which may limit such analgesics’ potential to relieve

(D) an effect that may limit their potential to relieve

(E) an effect that may limit the potential of such analgesics for relieving

Source  :  The Official Guide to GMAT, 1984

GMATPill · Accepted Answer

With this question, you should spot the "comma" in the middle of the sentence with the word "which" next to it.

There are two considerations when evaluating "which." 
1) Structural
2) Meaning

The way the sentence is structured, "which" is describing "patients."  That's just what the structure of the sentence dictates. But from a  meaning perspective , you are trying to describe "psychological disturbances"--not "patients." Since structurally the word "which" is incorrectly describing "patients" we need to change the sentence structure. Therefore (A), (B), and (C) are wrong and now it's between (D) and (E).

Reading (D) we have:

"In large doses, analgesics that work in the brain as antagonists to certain chemicals have caused psychological disturbances in patients, an effect that may limit  their  potential to relieve."

You see the phrase "which may limit their potential to relieve severe pain."

There are multiple plural words here so we don't know what "their" refers to---does it refer to psychological disturbances, analgesics, or chemicals? Sure you could probably figure out which one it is, but from a structural standpoint, it is not clear which word "their" refers to. Therefore, you must reword the sentence so that it is clear what "their" refers to. 
(D) looks unclear so let's look at (E).

(E) an effect that may limit the potential of such analgesics for relieving
This answer choice gets rid of the ambiguity associated with the word "their" and it also does not use the word "which"--which is positioned to incorrectly describe "patients." Although (E) is longer than the other answer choices, it is free of error.  Therefore, (E) is correct.

sid3699 · Answer

E.

Which is incorrectly used to refer to the patients. It is the effect of the disturbances that may limit the antagonists from relieving the pain.

GMAT TIGER · Answer

"Which" in A, B and C is incorrect.

"Their" could refers to "analgesics", "certain chemicals", "psychological disturbances", and "patients". So it is unclear.

In E, "such analgesics" clearly refers to "analgesics". Therefore E is correct...

Shrey08 · Answer

Hello  daagh  sir,

I selected C as the right answer thinking that " which " can jump over essential modifier " in patients " and modify " psychological disturbances ".

Can you please explain why it's wrong?

daagh · Answer

1984 question ---We must ignore such outdated examples and go in for more current issues.

krndatta · Answer

EducationAisle

Which in options A,B, and C can refer to psychological disturbances? 
"which" modifies the near grammatically eligible word that makes sense. 
Psychological disturbances can limit such analgesic's potential to relieve. 
Further more what is wrong with the possessive (Analgesics')  in option C?

Please elaborate.

ParamjitDasGMAT · Answer

Hi  krndatta ,

Psychological disturbances   themselves aren't going to "limit" anything. Patients' getting/contracting this malady is going to have a limiting effect, and there is no real way for a relative modifier in "which" to refer to this whole idea.

Hope this helps.

krndatta · Answer

ParamjitDasGMAT ,

Analgesics have caused psychological disturbances in patients, which may limit their potential to relieve severe pain.

Sir, 
In the above statement, the meaning is that analgesics potential to relieve sever pain is limited. 
Am I right? 
However,  "their"  has multiple antecedents. Hence we eliminate options A and B. 
Furthermore in options A, B, and C "which" is incorrect because "which" cannot refer to the whole idea. "Which" can refer to a noun.
Hence, we eliminate options A,B, and C.

Option D:- Same error of "their" above. 
Option E:- This is the correct answer.

Please evaluate my reasoning for the above options.

I want to understand further that in option C, why is "analgesic's potential" wrong?

Please elaborate on that.

nayas96 · Answer

Isnt "for relieving" unidiomatic ?
 daagh   GMATNinjaTwo   GMATNinja

Kindly please clarify

ParamjitDasGMAT · Answer

Hi  nayas96 ,

No, it's not. Either of the following is correct:

Potential to  +  do something (infinitive form of the verb)  OR
 Potential for  +   doing something (gerund form)

Hope it helps.

Posted from my mobile device

ExpertsGlobal5 · Answer

Hello  nayas96 ,

We hope this finds you well.

To answer your query, both "potential + infinitive verb form ("to + base form of verb")" and "potential + for" are idiomatic constructions.

We hope this helps.
All the best!
Experts' Global Team

alex73195 · Answer

Why cant it be D? I feel like it is unambiguous.

Sentence Correction #1 LIVE with GMAT Ninja: "Next-level" GMAT pronouns on Youtube  17  minutes discusses this.

ExpertsGlobal5 · Answer

Hello  alex73195 ,

We hope this finds you well.

To clarify, Option D does, indeed, suffer from pronoun ambiguity because "their" can logically and grammatically refer to both "analgesics" and "certain chemicals".

Although "analgesics" is the more logical referent, "certain chemicals" is not an illogical referent.

We hope this helps.
All the best!
Experts' Global Team

Ayushi0002 · Answer

In option D - their would be unambiguous, but I recently saw an example from GMAT Ninja - clearly stating that if the subject is clear in the first half, the pronoun can refer to it unambiguously.

Though yes, since E is clarifying it delibrately with ‘such …’ we can go but I still am not sure of the clear reason to eliminate D.

In large doses, analgesics that work in the brain as antagonists to ce

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GMAT Sentence Correction (SC - EA only) Questions

In large doses, analgesics that work in the brain as antagonists to ce

Prep Toolkit

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