The number of workers in this factory a lot this year. There were only a few workers in

问题补充：

The number of workers in this factory a lot this year. There were only

a few workers in it two years ago.

A. have increased

B. has increased

C. have risen

D. has booked

答案：

A. have increased

(答案→)B. has increased

C. have risen

D. has booked

解析：考查固定搭配。The number of作主语，谓语动词用第三人称单数，故排除A和C.句意：这家工厂工人的人数今年增加了很多，两年前，仅仅有几个工人。根据句意排除D。