<span>the word that the appositive renames or further identifies - agent</span>
I'm thinking Huck Finn, and Of Mice and Men are similar, just by the dialogue, if not by the mannerisms of some of the characters.
I don't know if that answers the question but, hey; I tried. :-/
Answer:
D, I believe it is.
Explanation:
It makes sense to be the correct answer to highlight the livelyness of the environment.