You'd better ________ when you come in.

A.not to wake him up

B.not wake him up

C.to not wake him up

D.not waking him up

答案及解析： B

解析：

had better是复合情态动词，后面只能跟不带to的不定式；

其肯定或否定意思是通过不定式的肯定或否定形式来表达的，表示否定意思时，在不定式前加not。