一道很怪的语法，请教！

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 to buy First Interstate Bank until a merger agreement be signed by them with a provision for penalties if the deal were

我选择了A，虽然A中的that includes没有B中的with短语简洁，但我的疑问主要是B中的be done的用法，是否可以省略would之类的词语，因为if之后使用的是虚拟语气；

多谢各位NN；

Oasiswater，

偶在原题目上加了下划线，请以后发帖尽量加下划线，这样大家看起来会比较方便。

另，能不能把题目补全先？

谢谢！

Agree with LES.

And, even there is an omitted WOULD, option B is wrong. As UNTIL is similar with IF, with which a clause cannot implement future tense. A WOULD is therefore invalid.

Your comments will be appreciated.

多谢楼上两位，多谢LES帮我划了一下。

剩下的三个答案存在很明显的错误的，所以偶就没有输入，因为无法copy，所以就把两个迷惑的答案挑出来了，偶也认为B中表达的不合理，可答案给的是B，所以就想让各位nn给分析一下，看是不是我老眼昏花看不出来了？

偶觉得本句中的until不可换成if，因为本句子是一个not until引导的大的结构，not放在句首，until直到中间才出现，同时if是虚拟语气；

请指教...