GMAT Sentence Correction (SC) | Re: Australian embryologists have found evidence that suggests

Although correctly in the answer choice E, 'It' referring to elephant and parallelism issue are not enough to eliminate the other answer choices easily.
This question relates more to verb tenses.

A) elephant is descended (correct), and its trunk originally evolving. Wrong (and should create another complete clause - verb is evolving - wrong verb tense)
B) evidence has suggested --- Suspect. Elephant descended (Simple past tense - wrong usage). trunk originally evolving (Wrong)
C) evidence suggesting
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