All of these letters and telegrams,almost without exception,urge that the cause we have been fighting for___ A.be carried on B.being carried on C.carrying on D.to carry on
答案：A be carried on
all urge that.
主语 谓语 宾语从句.
the cause should be carried on.表命令请求建议的宾语从句里用should do,但是should 可以省略
we have been fighting for the cause.是定语从句 引导词that被省略