Meaning of "you did all the talking" and "I'm biting" in argument

Considering the following situation. There are A, B and C three persons involved. A keeps telling B someone's bad words without mentioning who it is in presence of C. C feels like A is talking about him and keeps listening without saying anything. After quite a while C talks to B in presence of A "I am feeling personal attack. Not replying to A, doesn't mean feeling afraid but not worth it." A then replies "no comment. you did all the talking." After a short moment, A breaks the silence and says to C "okay, C, I'm biting. bla bla ..." followed by some defense for A himself.

My questions are:

1. What kind of sentiment is behind A's "no comment. you did all the talking."? What does A actually mean? Could A mean "what you said manifest you are that person I was talking about and no need I say who it is now" or "what you said has nothing for me to reply to" or "I won't join your talk because I don't think it is worth me to" or anything else?

2. What does A mean by "I'm biting"? Is it like "Yes, I am verbally attacking you", or "I am taking back what I said earlier about 'no comment.you did all the talking.' Now I am starting to comment" or something else?

Thanks and regards!