-- Who is dancing to music in the next room?-- the children.A. It isB. They areC. That is

问题补充：

-- Who is dancing to music in the next room?

-- the children.

A. It is

B. They are

C. That is

D. There are

答案：

(答案→)A. It is

B. They are

C. That is

D. There are

解析：此题考查代词it 的用法。句意：在隔壁谁伴着音乐跳舞呢？是孩子们。在不知道性别或多少人，什么样的人等时，常用it 来代替。所以选A。