一道英语选择题 I really don't know .......

Question

题目 ：I really don't know ------the problem.
A what to solve (这个我知道肯定错的)
B how to solve
C why to solve (这个也是错的吧 ，，)
D who to solve
主要是 B D 有点纠结 ， 我们老师说 选D 但我觉得B好像不错吧 。求详解 。。。:-D 额 ，顺便把涉及的知识给我想一下 ， 对这类的选择题一直失分。

Answer 1

B how to solve 是对的
没有who to solve the problem的用法。如果想表达“不知道让谁来解决这个问题。”是I really don't know who we should ask to solve the problem

Answer 2

选B啊
Examples:

I don't know how to open my computer.
I don't know how to excel at my class.
I don't know how to live my life without you.
and so on...

Answer 3

I really don't know ,how to solve the problem
我真的不知道,如何解决这个问题

Ireally don't know ,who to solve the problem.
我真的不知道,谁来解决这个问题。应该都对。

Answer 4

B .
D 答案不需要加to的
这种题型，可以把前面的主句I really don't know 去掉来解答，这样看就简单多了

Answer 5

选B,第四个答案可以把to 换成will 还可以说通。