一个九位数，最高位是最大的一位数，十万位和百位上的数都是最小的质数，其余各位上的

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。（10分）

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:   小题1: 
B: Hello, Li Lei.    小题2: 
A: I’m doing my homework.
B: I think you are learning physics.
A: Yes. You’re right.  小题3:
B: Because physics is your favorite subject.
A: David, we want to play soccer this afternoon.   小题4:
B: Yes, I’d love to.   小题5:
A: We want to meet on the playground at 1:00 p. m. See you then. Bye.
B: Bye-bye.