At that time I had no idea ________ I could hand it to him without being see

Question

At that time I had no idea ________ I could hand it to him without being seen. A. if B. how C. which D. that how 选B为什么不选D

Answer 1

名词后面加idea一般表示同位语从句，用于解释idea的内容。
而此题的意思是当时我不知道自己该怎样把东西交给他。
故用how表示怎样，用that就会显得多余且意思误差。

Answer 2

have
no
idea=
don't
know
（
不知道
）
其后可直接跟
特殊疑问词
引导的
陈述句
。
译文：那时，我不知道怎样才能偷偷地将东西交给他。