选句子补全对话，把序号写在横线上。

A. Three times a week.  B. I play ping-pong for three hours. C. I do well in my study. D. Yes, I do. E. I'm playing ping-pong.

Kevin: What are you doing, Su Nan?

Su Nan:

Kevin: Do you often play ping-pong?

Su Nan:

Kevin: How often do you play it?

Su Nan:

Kevin: How many hours do you play every time?

Su Nan:

Kevin: How about your study?

Su Nan: