根据短文内容，从短文后的选项中选出能填入空白处的最佳选项。(选项中有一项为多余选项。)

A: Good morning, Andy.

B: Good morning, Alice. Why do you look unhappy(不高兴)?

A: I like it so much.

B: Oh! l found a book on the playground(操场). Is it yours?

A: No, it isn't.

B: . Are they yours?

A: No, they aren't. They are blue and mine are yellow.

B:

A:I don't know(我不知道). Henry's phone number is 367-1873.

B: OK. Thank you, Alice.

A:

A. Because I can't find my book. B. You can call him. C. You are welcome. D. What color are these? E. What about these pens? F. Are these Henry's pens?