A、Because she has been ill for a week. B、Because she failed to pass the exam. C、Because she had an unpleasant experience with a

M: Hello, Cathy, it’s been a long time since we last met. How are you?
W: Not too bad.
M: Tell me what’s happened, you don’t look so happy as usual.
W: Well...you know what? I have had a terrible experience with a burglar. And I was so terrified that I failed to prevent him.
M: Oh, my! Where did the burglary happen?
W: In our students’ dormitory.
M: Would you please tell me in detail?
W: Well, I’m not sure I can remember all the details, but it happened about 6 p.m. yesterday, and I saw a man walking up the stairs.
M: What did you do then?
W: Well, I didn’t recognize him and I became suspicious, so I followed him...
M: Then what happened?
W: Well, I got frightened and tried to find someone for help. But while I was gone, he got away with quite a lot of money and a cassette recorder.
M: Why didn’t you follow him into the bedrooms?
W: I should have followed him, I know. If I had raised the alarm earlier or tried to stop him, I suppose I might have prevented the theft. Now I feel so sorry for my fault.
M: Oh, it’s not your fault. Cathy, you don’t have to blame yourself. After all, you are still a fragile girl and it would have been dangerous for you if you angered the ruthless burglar. In my opinion, it’s the school’s security department who is to blame.