-- Where are the?-- They are on the desk.A. bookB. pensC. mapD. water

问题补充：

-- Where are the?-- They are on the desk.

A. book

B. pens

C. map

D. water

答案：

A. book

(答案→)B. pens

C. map

D. water

解析：根据are和They可知，此空应该是一个名词的复数形式，选项中只有B。所以本题选B。