Some one correct me if I am wrong.

distinguish X from Y, for X and Y that are similar

distinguish original painting from a fake painting. But both of them are paintings

Distinguish between X and Y, for X & Y that are different.

distinguish between cats and dogs (We can distinguish between cats and dogs even though both of them are similar in that they are animals)

Here X & Y are mood swings and manic depression.

To me, between X & Y is the correct usage here and hence C

Even if we think mood swings and maniac depression are similar, what is their in A referring to? mood swings are already referred to by which.

What is OA?

HI ChidGuy,

I think which in option A modifies the mood swings(which seems 2 be ok).
In this case the doctor distinguishes X(moods swings) from Y(psychosis) makes more sense than distinguishes between X(moods swings) and Y(psychosis).

Please correct me if i am wrong

IMO A.

IMO A too....

First it sounds good and the same logic.

But I remember the GMAT Experts of BEAT THE GMAT ONCE SAID THAT THE CHANCES OF THIS KIND OF QUESTION COMING IN THE ACTUAL GMAT ARE LESS AS BOTH EXPRESSIONS DISTINGUISH A FROM B AND DISTINGUISH BETWEEN A AND B ARE IDIOMATIC.

IMO A:

A and C are close but if I have to choose,
then if it takes research to analyze the difference, then they are more likely to be considered alike before (Although not very convincing). And thus "distinguish X from Y" seems better here instead of "distinguish between X and Y".

The answer for this question is C. I know it's kinda close call between A and C, but as "chidcguy' pointed out, "their" seems little odd in that sentence.

One thing I wanted to get out of this post was, when you should use the idiom "distinguish x from y" vs "distingusih between x and y". Can we go with chidcguy's analysis that distinguish from" is used when comparing similar items? Can anyone else weigh on this?

ildude02 wrote:The answer for this question is C. I know it's kinda close call between A and C, but as "chidcguy' pointed out, "their" seems little odd in that sentence.

One thing I wanted to get out of this post was, when you should use the idiom "distinguish x from y" vs "distingusih between x and y". Can we go with chidcguy's analysis that distinguish from" is used when comparing similar items? Can anyone else weigh on this?

"chidcguy" conclusion is 100% correct. There is Pronoun Reference Error in the option 'A'.

I agree with childcguy.

Imo C

Can someone please elaborately explain the difference between A and C.

cz in spite of the above explanations to me both seem to be same

hi nitin9003
i try to say something about A and C
both idioms distingiush X from Y, and distinguish between X and Y are correct, and it is not an issue here, i guest that former is slightly inferior as i often saw that they prefer to use distinguish x from y in a very short expressions
as for example
distinguish apples from oranges,
but when whole construction is long with relative clause:mood swings, which may be violent ........they prefer distinguish between x and y.but i am not 100% sure
the problem in a is with possessive pronoun their, it has no valid antecedent, as possessive pronouns can apply only to nouns that are in possessive case, but not in subject or object cases
distinguishes mood swings objective case....without their-possessive case
for clear reference you can apply to the MG sentence correction 4 edition page 70

ans is 3 IMO

I'd say the main issue with A is that it's less parallel in the relative clause: which may be X without their being Y, as opposed to choice C's which may be X without being Y. (I think this is also what clock60 was saying). Both uses of distinguish are correct, as it may be transitive or intransitive.

IMO A

there is no difference between A and C

distinguish A from B is valid

distinguish between A and B is valid