sevenplusplus
Can GMAT throw an option which is "correct" and just a little wordy ( a couple of redundant words)?
There has to be, in my view, more reason than just wordiness for C to be not a correct choice.
I think that the GMAT draws a distinction between redundancy and wordiness. I actually agree with you in general: "wordiness" isn't, by itself, a very compelling reason to eliminate an answer choice. In most official questions, there's something stronger than "wordiness" that allows you to eliminate the wrong answer choices.
(And yes, I know that the OG explanations often dismiss wrong answers as just "wordy" or "wordy and awkward." But the OG explanations are notoriously lazy, and weren't written by the same people who wrote the questions. In the overwhelming majority of cases, you can find a better reason for the elimination than just "wordiness". And I'd also argue that tons of right answers are pretty darned wordy... but that's not helpful.

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But redundancy is a different thing. If something is repeated unnecessarily, that's just wrong on the GMAT. There are official questions that squeeze the phrases "last year" and "annually" into the same sentence -- that's always wrong. There's another question that uses the phrase "has the ability to" and "to be able to" in the same sentence. That's unambiguously wrong, too.
To be fair, this (non-official!) question probably blurs the line a little bit between "wordiness" and "redundancy." If the ONLY difference between (C) and (D) is a couple of unnecessary words, I guess I'll always pick the one that doesn't have those unnecessary words. But official GMAT questions will usually give you something meatier to work with.