[求助]一道PREP SC题 原PREP破解里没有这题

Not one of the potential investors is expected to make an offer to buy First Interstate Bank until a merger agreement is signed that includes a provision for penalties if the deal were not to be concluded.

A. is expected to make an offer to buy First Interstate Bank until a merger agreement is signed that includes a provision for penalties if the deal were

B. is expected to make an offer for buying First Interstate Bank until they sign a merger agreement including a provision for penalties if the deal was

C. is expected to make an offer to buy First Interstate Bank until a merger agreement be signed that includes a provision for penalties if the deal were

D. are expected to make an offer for buying First Interstate Bank until it signs a merger agreement with a provision for penalties if the deal was

E. are expected to be making an offer to buy First Interstate Bank until they sign a merger agreement including a provision for penalties if the deal were

PREP破解里没有这题,应该是新的吧.哪位NN帮解释一下?答案是A