His success the fact he had been working hard. A. put in; which B. led to; because C. la

问题补充：

His success the fact he had been working hard.

A. put in; which

B. led to; because

C. lay in; that

D. got in; that

答案：

A. put in; which

B. led to; because

(答案→)C. lay in; that

D. got in; that

解析：lie in在于，that引导一个同位语从句。put in(正式)提出、花费(时间)、插话、安装； lead to导致、结果；get in到站、当选、插话、上车、请来、加入。若单看第一空，lead to也对。