I would have told him the answer had it been posible ,but I ____so busy then.A had been B were C was D would be请问选什么为什么,

问题描述:

I would have told him the answer had it been posible ,but I ____so busy then.
A had been B were C was D would be
请问选什么为什么,

C was
I would have told him the answer had it been posible ,为虚拟语态,而but I ____so busy then.为非虚拟语气,then提示是过去,故选was