Thanks to my teacher's valuable help otherwise I my college entrance exam.A. can't pass

问题补充：

Thanks to my teachers valuable help, otherwise I my college entrance exam.

A. can pass

B. hadn passed

C. would not have passed

D. have not passed

答案：

A. can pass

B. hadn passed

(答案→)C. would not have passed

D. have not passed

解析：C 考察虚拟语气。由语境可知，幸亏老师给我的巨大帮助，否则我不可能通过高考，前面从句相当于一个与过去事实相反的虚拟条件句，因此后面的主句谓语动词应该是would/could/might/should have done。故C正确。