is often the case is that Tom doesn’t study hard and fails in passing an exam.A. ThatB. A

问题补充：

is often the case is that Tom doesn’t study hard and fails in passing an exam.

A. That

B. As

C. It

D. What

答案：

A. That

B. As

C. It

(答案→)D. What

解析：考察名词性从句。What引导主语从句What is often the case，并在句中作主语。本题容易错选B。as引导的是非限制性定语从句，指代一句话的内容在句中充当成分。