听力原文：How much time in advance does David usually get to his office?
(21)
A.50 minutes.
B.60 minutes.
C.10 minutes.
D.15 minutes.

A.50
B.
B.60
C.
C.10
D.
D.15
E.

【参考答案】

C
解析：David说他基本上每天都是8:50到办公室，而他公司每天9点正式上班，故选C。