The number of people invited fifty but a number of them absent for different reasons.A. w

问题补充：

The number of people invited fifty, but a number of them absent for different reasons.

A. were, was

B. was, were

C. was, was

D. were, were

答案：

A. were, was

(答案→)B. was, were

C. was, was

D. were, were

解析：the number of指“……的数目”，它所修饰的主语的谓语动词用单数；a number of= many,它所修饰的主语的谓语动词用复数。故选B。