One more week-----------we will accomplish the task.A.all B.

and因为这是一祈使句的缩写形式.即祈使句+ and/or+简单句.这里的祈使句就缩写成了名词短语,所以这句相当于 Give us one more week and we will accomplish the task.再给我们一周我们就能完成任务.
再问： 为什么不能用so that？
再答： so that不用于此句型中。给你个例子 He got up early this morning so that he could catch up with the early bus.(so that以便，为了，引导目地状语从句，从句中常有情态动词may/can)