—Listen! Someone is playing the piano.—Wow! beautiful music! I like it very much.A. WhatB

问题补充：

—Listen! Someone is playing the piano.

—Wow! beautiful music! I like it very much.

A. What

B. How a

C. What a

D. How

答案：

(答案→)A. What

B. How a

C. What a

D. How

解析：感叹句。感叹句由how或what 引导。 其结构分别为“How+adv\adj+主语+谓语！”“What+a\an +adj+n+主语+谓语！”“What+adj+名词复数\不可数名词+主语+谓语!”。把结构代入可知答案为B。