How much did it cost to build the science lab? Five yuan.A. millions B. million C. millio

问题补充：

How much did it cost to build the science lab? Five yuan.

A. millions B. million C. millions of

答案：

解析：句意：建设科学实验室花费多少钱？五百万元。Million百万；在具体的数字里不用复数形式，如three million；但在短语millions of数百万，要用复数形式；故选B。