this( )is very difficult.I can't work it out.

问题描述:

this( )is very difficult.I can't work it out.
Amath Bphysics Cquestion Dproblem
最好要有翻译.
再解释完这道题目后请详细说明这四个的用法与区别

C
这个( )太难了,我不能算出来
Amath数学 应该是数学题math problem
Bphysics 物理同上
Cquestion难题
Dproblem问题
最符合题意啊
懂了吗