If you've located three books on a topic you're researching for an essay, the first thing you should do on appraising any of these books is

A. examine the index.

B. scan the book from front to back.

C. study the table of contents.

D. inspect the book jacket for notes about the author.

I would probably say - - - A. examine the index.---

it might be C but I'm leaning more on the A side

So the question is asking to choose among the following choices that first thing that you should do on appraising any of books that contains the topic that you're researching for, and base on the said question, I would say that the answer would be letter A. examine the index. I hope you are satisfied with my answer and feel free to ask for more