"Keep," this is because the adverb always modifies the verb, and a verb is a action, and keeping is an action.
Answer:
I think its D or A based on the information
D. third person voice and present tense verbs.
You use 3rd person because it is more formal. The teacher always says "don't use I!"
You use present tense to talk about the book because even though you as the writer already read the book, the person who is reading your analysis may not have read the book, so use present tense. For example, you should write, "The book states on page" instead of "The book stated on page"
