The question that should be asked when characterizing the antagonist is "How do others respond to the antagonist?" Option A is correct.
An antagonist is the character in a story who is against the protagonist.
The antagonist is opposed to, struggles against, or competes with another; opponent; adversary, in literature, it is the adversary of the hero or protagonist of a drama or other literary work.
The English word antagonist stems from the Greek antagonistēs.
Are there options to chose from?
I need the entire sentence for context before I can answer the question. All of these options could be a subject, but you need to give context.