17   Not one of the potential investors is expected to make an effort to buy First Interstate Bank until a merge 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 merge 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 merge agreement including a provision for penalties if the deal was
C.        is expected to make an offer to buy First Interstate Bank until a merge agreement be signed by them with a provision for penalties if the deal were
D.        are expected to make an offer for buying First Interstate Bank until it signs a merge agreement with a provision for penalties included if the deal was
E.        are expected to be making an offer to buy First Interstate Bank until they sign a merge agreement including a provision for penalties if the deal were
这题答案是A我选了B，本来想选A， 但觉得 the deal were不对，这里为什么要用were?

这里用 were 是 subjunctive，B 那个 was 是用错 indicative mood 的时态。还有，B 的 make an offer for buying 不顺。

Thank you.
语法知识都还给老师了好像
看白勇也没见有

在虚拟语气的从句中，动词'be'的过去时态一律用"were"，不用was， 即在从句中be用were代
If he were here, everything would be all right.
　　如果他在这儿，一切都会好的。

我*，这道题不选C么？

C 就是那个 be 不对。在这个语境里面，until 之后不是用 subjunctive 的。