GMAT Sentence Correction (SC) | Re: Jane was with the impression that John needed her help.

Hey,
The correct idiom is "under the impression" , hence we can eliminate A & B
Now, among C,D,andE
E changes the meaning , a bit ( the original sentence says Jane thought john needed her help ", while E says "Jane thought john needed help")

now between C & D
They both deliver the same message as the original sentence but, C is more concise
D is wordy

Hence C
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