-Would you like to sing a song for us?
- .
A. I prefer not
B. I prefer not to
C. I prefer to not
D. I wouldn't prefer
网友回答
A. I prefer not
(答案→)B. I prefer not to
C. I prefer to not
D. I wouldn't prefer
解析：选项A的not可以代替的是句子；B项not to代替不定式动词，相当于prefer not to sing a song。