Mark the letter A, B, C or D on...

Câu hỏi: Mark the letter A, B, C or D on your answer sheet to indicate the sentence that is closest in meaning to each of the following questions.
You must clean the wall before you painted it.

A. The wall must be cleaned before you paint.

B. The wall must clean before you paint it.

C. The wall must be clean before you paint it.

D. The wall must be cleaned before being painted.