B: at 6 o'clock, I, morning, in, go to bed, the (.)

① What are they doing?      A. She’s sitting under a tree.

② Do you see a cat?     B. He is cleaning his room.

③ What's Mike doing?      C. Yes, I do.

④ Where is Amy?     D. They are watching TV.

A.     B.      C.     D.