Question

The number of books in the bookshop is about 10,000 and a number of them
     about science.

A．is

B．was

C．are

D．Were

Answer 1

C

考查动词的用法。依据第一句中的谓语动词“is（一般现在时）”可推断出第二句的时态也应是一般现在时，故保留A和C项；由短语“a number of...”的谓语动词是复数，故选C。