问题

_____ that he picked up his uncle at the airport—It was at 6:00 in the afternoon _____ he got offwork
A:If we didn’t wait for
B:If we haven’t waited for
C:we hadn’t waited for
D:Had we not waited for
B:If we haven’t waited for
C:we hadn’t waited for
D:Had we not waited for
正确答案是: