问题

I was trying to carry out the plan, but I failed.—Well, you _____, for we were uncertain it would do ____.
A:needn’t do that, in fact
B:needn’t have done, in effect
C:needn’t have, in practice
D:needn’t, in time
B:needn’t have done, in effect
C:needn’t have, in practice
D:needn’t, in time
正确答案是: