the arrival of the police I would have been robbed by two masked men.A. Had it not been

问题补充：

the arrival of the police, I would have been robbed by two masked men.

A. Had it not been for

B. If it were not for

C. Had it been not for

D. If it would not be for

答案：

(答案→)A. Had it not been for

B. If it were not for

C. Had it been not for

D. If it would not be for

解析：A 考察虚拟语气。句义：要不是意为警察赶到，我就被那两个蒙面人抢了，与过去事实相反的时候，从句使用过去完成时，主句使用情态动词+have done。从句中省略了if还可以使用部分倒装的学生。