Sentence Correction

Guys, regarding the attached question, I narrowed down the answer choices to two - C and E. But the official answer to this problem is E.

Is the answer to this problem SOLELY based on the ground of before--after relationship?

I was wondering why the option "C" is not the best answer. I considered that "......yields this year" would require a past(passive)--present tense relationship rather than a past perfect(passive)--past tense relationship.

Any insights? I Appreciate your support very much!

The agriculturist appears confident that her study will show that several crops that were damaged during last year's drought failed to produce sizable yields this year.

A.several crops that were damaged during last year's drought failed
B.several crops that were damaged during last year's drought fail
C.several crops that were damaged during last year's drought have failed
D.several crops that had been damaged during last year's drought fail
E.several crops that had been damaged during last year's drought failed - Parallel

IMO: E