选择合适的句子完成对话。

A. She's doing her homework.            B. He is reading books. C. She is watching TV.              D. No, I'm making a model plane.

Ben: Look, this is my family photo.

 Kitty: Wow! So many people. What is your mother doing?

 Ben:

 Kitty: Is your father watching TV, too?

 Ben: No, he isn't.

 Kitty: What is your sister doing?

 Ben:

 Kitty: Are you doing your homework, too?

 Ben: