听力原文:M: Ordinarily you never seem to be nervous. But why were you so nervous just now
W: You know, I didn't enter my house until I found my key at 11 o'clock last night, so I didn't have enough time to preview my lessons.
Q: Why did the woman feel nervous?
(15)
A.She was afraid of the professor.
B.She didn't enter her house.
C.She didn't make full preparations for her lessons.
D.She lost her key.