问题补充：
—Listen! Our music teacher is playing the music of Two Butterflies.
—!
A. What a sweet music
B. How sweet music
C. How a sweet music
D. What sweet music
答案：
A. What a sweet music
B. How sweet music
C. How a sweet music
(答案→)D. What sweet music
解析：以what引导的感叹句的基本句型结构为what a/an +adj+可数名词单数+主语+谓语！；what+adj+可数名词的复数/不可数名词+主语+谓语！以how引导的感叹句的基本句型结构为how+adj/adv+主语+谓语！
