单项选择题

M: Thank you very much, Miss Times. That helps me a lot.
W: I am glad I could be of some help, Carlos. Let me know if you have any more questions later.
M: I will. I thank you for giving up your coffee break to help. I know you need one after teaching three classes.
W: Oh, I don’t mind. Teaching is what I love most.
M: Well, goodbye and thanks again.
W: You are very welcome, Carlos. See you on Monday class.

Why does the man thank the woman()

A. She has helped him with his problem.
B. She has invited him for coffee.
C. She has agreed to see him on Monday.
D. She has agreed to give him some coffee.