Although the phenomenon of withdrawal has always been the crucial phys

Even though this is tagged as a sub-600 question, it can pose a lot of confusion if you are not familiar with idioms that are used in comparisons.
Plus, if you are in the habit of second-guessing yourself, you might find Option B tempting.

Let’s simplify the sentence –
Withdrawal has been the crucial Leng for distinguishing X from Y drugs.
This seems to be the correct structure, so let’s hold onto Option A and have a look at the rest.

B – this is the wrong idiom. It is ‘distinguishing X from Y’. Eliminate.
C – the ‘or’ changes the meaning – addictive or non-addictive is not what is intended here. They do not mean the same thing. Eliminate.
D – the ‘or’ is not the right way to compare two items in this case. Eliminate.
E – wrong idiom again. We are trying to distinguish one thing from another. Eliminate.

Option A is the best choice.

Hope this helps!

Dear Friends,

Here is a detailed explanation to this question-



A: This answer choice maintains proper idiom use throughout the sentence. Thus, this answer choice is correct.

B: This answer choice utilizes the unidiomatic construction "distinguishing A and B", rather than one of the correct constructions "distinguish between A and B" and "distinguish A from B". Thus, this answer choice is incorrect.

C: This answer choice utilizes the unidiomatic construction "distinguishing A or B". Thus, this answer choice is incorrect.

D: This answer choice utilizes the unidiomatic construction "between A or B", rather than the correct construction "between A and B". Thus, this answer choice is incorrect.

E: This answer choice utilizes the unidiomatic construction "among A or B", rather than the correct construction "among A and B". Additionally, E uses the word "among" to draw a distinction between two nouns "addictive drugs" and "non-addictive drugs". Thus, this answer choice is incorrect.

Hence, A is the best answer choice.

To understand the concept of "Use of Distinguish on GMAT", you may want to watch the following video (~1 minute):



To understand the concept of "Between v/s Among on GMAT", you may want to watch the following video (~1 minute):



All the best!
Experts' Global Team

Hello from the GMAT Club VerbalBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.