补全对话： 根据所给对话，从方框中选出一个能填入空白处的最佳选项。

A. When and where will we meet? B. Why do you think so? C. This is Li Lei. D. What are you doing? E. Would you like to come with us?

A: Hello! May I speak to David, please?
B: This is David speaking. Who’s that?
A:    
B: Hello, Li Lei.     
A: I’m doing my homework.
B: I think you are learning physics.
A: Yes. You’re right.  
B: Because physics is your favorite subject.
A: David, we want to play soccer this afternoon.   
B: Yes, I’d love to.   
A: We want to meet on the playground at 1:00 p. m. See you then. Bye.
B: Bye-bye.