I think your correct for all of those answers.
Answer:
C. "In fact, they (vampire bats) might play a role in human health."
Explanation:
This answer has the most positive connotation towards vampire bats, as it would be a good thing for them to improve human health. Although the other answers don't make vampire bats seem terrible, C. is the best answer, which it even states it as a fact. Hope this helps!
