Mother: You don’t look happy, Cathy.               
Cathy: I didn’t do well in the chemistry test.
Mother: Really? I could hardly believe you were not doing well in chemistry.                    What happened this time?
Cathy:          I found all the questions easy and I finished the test in no time.
Mother: Yes. It is one of your weaknesses.
Cathy: Yes.            I made some very stupid mistakes that I shouldn’t have made.
Mother:              
Cathy: Yes, I have certainly learned a lesson.

A．I know you are very good at chemistry.

B．What’s wrong?

C．I was too careless.

D．I feel angry at it.

E. You are right.
F. Well, next time you should be more careful.
G. I don’t know.