Question

We had to stay at home ______ it was raining hard.

A．of

B．because

C．because of

D．as

Answer 1

B

解析试题分析：句意：我不得不待在家里，因为下很大的雨。Because因为，后接从句；because of因为，后接名词性短语；题中后面是个从句，故选B。
考点：考查连词。