给下列问句选择正确的答语。

① How many books do you have?     A. I bought a lot of books.

② What are the rabbits doing?     B. They are onions.

③ Can you play the piano?      C. I have twenty books.

④ What did you do last Sunday?      D. They are jumping.

⑤ What are these?     E. Yes, I can.