—What a nice classroom! —It every day.A. is cleaningB. has cleanedC. must cleanD. is clea

问题补充：

—What a nice classroom!

—It every day.

A. is cleaning

B. has cleaned

C. must clean

D. is cleaned

答案：

A. is cleaning

B. has cleaned

C. must clean

(答案→)D. is cleaned

解析：句意：多整洁的教室啊！它每天都被打扫。It指代classroom,教室，与谓语动词是被动关系，所以用被动语态:be+过去分词；故选D。