一到英语选择题The letter from his girlfriend he had been looking fo

一到英语选择题The letter from his girlfriend he had been looking forward to [ ] yesterday.A came B
The letter from his girlfriend he had been looking forward to [ ] yesterday.
A came
B comes
C coming
D come
请问选什么,以及为什么,还有不选其他的原因,还有本句话的翻译.