I’d like to have visited the Palace Museum but something unexpected to my father.A. had

问题补充：

I’d like to have visited the Palace Museum, but something unexpected to my father.

A. had happened

B. happened

C. has happened

D. happens

答案：

A. had happened

(答案→)B. happened

C. has happened

D. happens

解析：考查时态，句意是：我本想参观故宫博物院，但我爸爸发生了预料之外的事，would like to have done本想做…而没有做，说明happen是过去的事。选B。