—Why didn't you open the door for me?

—Sorry, dear. I             in the kitchen. I didn't hear you. [ ]

A. am cooking

B. cooked

C. was cooking

D. will cook

22．—I am travelling to Japan tomorrow, Would you please tell me about your experiences there ?

—         . Let’s discuss it over lunch.

A．In no case

B．By all means

C．That’s all right

D．That depends