题目内容：

听下面一段较长对话，回答以下小题。

1.Whose keys are these?

A. They are Jack’s.    B. They are Betty’s.

C. The owner hasn’t been found yet.

2.Why hasn’t Joe come to school?

A. He had a headache.

B. He hurt his arm,and he had to see the doctor.

C. He didn’t like school at all.

3.When does this conversation most probably take place?

A. In the early morning.

B. After classes in the morning.

C. In the evening.