A、  B、  C、  A所给出的问题是询问对方是否参加派对的反义疑问句，选项(A)的答案“我还没决定”是符合语境的恰当回答。要注意问句中的retirement和选项(B)中的tired在发音上有相似之处，以及问句中的part

Would you rather look for a jacket at the mall or order one online?
(A) Let’s wait in line.
(B) I didn’t see Jack there.
(C) I’ll look at the mall first.

You’re going to Janice’s retirement party, aren’t you?
(A) I’m not sure yet.
(B) She’s usually tired after work.
(C) We haven’t gotten to that part yet.