听第8段材料，回答第11至第13三个小题．现在你有15秒钟的时间阅读下面三个小题．
11．How long has the boy been late today？

B

B

A．More than one hour．
B．One hour．
C．Less than one hour．
12．What's the relationship（关系） between the boy and the woman？

C

C

A．Mother and son．
B．Sister and brother．
C．Teacher and student．
13．Why didn't the boy hear the alarm？

B

B

A．He didn't turn it on．
B．He was asleep when the alarm went off．
C．The alarm clock was broken．