The piano is so nice that the girl is anxious __it .A of that B for it ,Cabout it D to that

问题描述:

The piano is so nice that the girl is anxious __it .A of that B for it ,Cabout it D to that
选哪,为何?

C about
be anxious about sth,这是固定搭配,没有原因,记住就好了.