单选题Since time began, it

单选题 Since time began, it seems, people have been putting off______they______have done today, scolding themselves in the meantime．A.that, mustB.that, shouldC.what, couldD.what, would

C解析句意是：自从时间开始，人们一直推迟他们本可以今天做的事，同时又会责备自己。第一空用what引导宾语从句，做do的宾语，第二空填could，表示虚拟语气，could have done是本可以做却没有做。选C。

就是这个解释