Recently physicians have determined that

[vrajesh.dave]

Recently physicians have determined that stomach ulcers are not caused by stress, alcohol, or rich foods, but a bacterium that dwells in the mucous lining of the stomach

B. not caused by stress, alcohol, or rich foods, but are by
C. caused not by stress, alcohol, or rich foods, but by
D. caused not by stress, alcohol, and rich foods, but
E. caused not by stress, alcohol, and rich foods, but are by


OA: C

I know it is an idiom error. Proper idiom goes "not X..., but (also)(rather)(by) Y"

So I guess, that makes C as the correct choice.

My question is, ulcers is plural so is "are" implied when the sentence goes like
"...ulcers caused not by...., but (are) by"

or we do not need to use plural form here after but ??

Instructor can you please clear this issue for me.

[rags99]

dude.. did u miss the "ARE" before the underlined portion of the sentence..;)

[RonPurewal]

dude.. did u miss the "ARE" before the underlined portion of the sentence..;)

good call

[vijayjakhotia]

Option B: not caused by stress, alcohol, or rich foods, but are by

Can someone point out why option B is incorrect?

ulcers are not caused by stress, alcohol or rich foods, but are (caused) by a bacterium....

Its similar parallelism as explained in MGMAT Pg:160 Not....But idiom

[jnelson0612]

Option B: not caused by stress, alcohol, or rich foods, but are by

Can someone point out why option B is incorrect?

ulcers are not caused by stress, alcohol or rich foods, but are (caused) by a bacterium....

Its similar parallelism as explained in MGMAT Pg:160 Not....But idiom

If you look at the first post, it lays out the idiom nicely.

The idiom is "not X but Y". You are not allowed to insert an "are" in this idiom. The "X" and the "Y" elements are actually what need to be parallel, and they are in this case:
X--stress, alcohol, or rich foods
Y--a bacterium

They are parallel in that they are all nouns and all possible causes of stomach ulcers.

[parekh.dhrumil]

I have a query in this type of formation. I understood the idiom part of the sentence. i.e "Not by....but by". But what if I were to add"by" at the end of answer choice "A", will it make it correct.

Note: there is still a difference between "caused not by" and "not caused by". So which one's correct. Please answer.

Thank you :)

[RonPurewal]

I have a query in this type of formation. I understood the idiom part of the sentence. i.e "Not by....but by". But what if I were to add"by" at the end of answer choice "A", will it make it correct.

actually, it appears you don't fully understand that construction.
the parallel signals are "not... but..."; the two instances of "by" are in the actual parallel elements.
if you have that understanding, the question below should be no problem.

Note: there is still a difference between "caused not by" and "not caused by". So which one's correct. Please answer.

Thank you :)

the parallel signals are "not... but...". just look at what comes after each of these signals.
in your construction, "not" is followed by caused by..., but "but" is just followed by by... -- not parallel.

[cumulonimbus]

Option B: not caused by stress, alcohol, or rich foods, but are by

Can someone point out why option B is incorrect?

ulcers are not caused by stress, alcohol or rich foods, but are (caused) by a bacterium....

Its similar parallelism as explained in MGMAT Pg:160 Not....But idiom

I have the same question and the explanation did not help.
Can anyone explain why is C better than B?

[RonPurewal]

Option B: not caused by stress, alcohol, or rich foods, but are by

Can someone point out why option B is incorrect?

ulcers are not caused by stress, alcohol or rich foods, but are (caused) by a bacterium....

Its similar parallelism as explained in MGMAT Pg:160 Not....But idiom

I have the same question and the explanation did not help.
Can anyone explain why is C better than B?

"Caused" (following not) is not parallel to "are" (following but).

You could have either of these:
caused not by X but by Y
not caused by X but caused by Y

[AsadA969]

Recently physicians have determined that stomach ulcers are not caused by stress, alcohol, or rich foods, but a bacterium that dwells in the mucous lining of the stomach

B. not caused by stress, alcohol, or rich foods, but are by
C. caused not by stress, alcohol, or rich foods, but by
D. caused not by stress, alcohol, and rich foods, but
E. caused not by stress, alcohol, and rich foods, but are by

The question is totally Parallelism issue. Here the correct answer is C. But, my question is: WHY not B. B makes parallelism to me!
B. NOT (tag)+CAUSED (verb)+by+something....................BUT (tag)+ARE (verb)+by+Something

[RonPurewal]

"caused" isn't a verb here.
in both parts, the verb is "are".