单项选择题

[听力原文]
W: Hello! How are you today
M: I’m feeling very nervous. I just had a test and I’m not sure how well or how badly I did.

Why does the man feel nervous()

A. Because he will have a test soon.
B. Because he doesn’t prepare for the coming test.
C. Because he didn’t finish the test he had yesterday.
D. Because he worries about his performance in the test he had today.