The reason their failure you know is they didn’t get fully prepared for the experiment.A

问题补充：

The reason their failure you know is they didn’t get fully prepared for the experiment.

A. why; that

B. that; why

C. for; that

D. why; because

答案：

A. why; that

B. that; why

(答案→)C. for; that

D. why; because

解析：考查介词及表语从句。“the reason for… is that…”是一个固定搭配。意为：．．．的原因是什么，for修饰the reason，that引导的表语从句，句意：他们失败的原因是他们没有充分准备好实验。因为the reason后面不是定语从句，不能用why。选Ｃ。