In the excerpt from "the negro artist and the racial mountain," in which sentence does hughes indicate that musicians and writers should work without any concern about judgment?

I believe this is the correct answer - An artist must be free to choose what he does, certainly, but he must also never be afraid to do what he might choose.
The other options don't really have much to do with the freedom or musicians and other artists, but rather with racial issues and problems that black artists face in a predominantly white world. However, the option I would choose states that these artists have to do what they want, regardless of the criticism they may get while pursuing their art.

A. An artist must be free to choose what he does, certainly, but he must also never be afraid to do what he might choose.