It's an infinitive, to + verb....
1) He is opposed to tbe idea of hunting humans
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In the passage is says ""But you can't mean_" Gasped Rainsford." He's surprised that General Zaroff actually intents to hunt humans.
Good luck,

Hyperbole because she says she dying it tell someone something, it’s an exaggeration
I think it's best if you read it again so I can make sense.
I think it is A: It makes clear to the reader that the narrator is making an ironic statement.