Government Funding of The Arts Discussion Assignment

I don’t know how to handle this Writing question and need guidance.

May the government refuse to fund speech (in this case, art work (symbolic speech)) that it could not ban because of the first amendment? May government   refuse to grant awards, such as those prestigious ones from the national endowment for the arts, to applicants whose art work has a message the government finds offensive or disagrees with?

Is this viewpoint discrimination? If so, and if the court generally rejects government use of restricting speech based on viewpoint, should government national endowment for the arts awards be an exception? If so, why?