---Do you like the Moonlight Sonata ？---Sure it sounds really .A. clearB. clearlyC. beau

问题补充：

---Do you like the Moonlight Sonata ？

---Sure , it sounds really .

A. clear

B. clearly

C. beautiful

D. beautifully

答案：

A. clear

B. clearly

(答案→)C. beautiful

D. beautifully

解析：sound是系动词，后跟形容词，构成系表结构。