It seems more sound to say their major point of discussion here is about popular music and whether it should reflect reality. Even though we can point out that whether reflecting a reality or not is an issue here, it make more sense to highlight the point of discussion to be more in line with the the issue that actually deals with the whole analysis. Having said this, it is clear that they are talking about art here, but it is also clear that they are not talking about art in general, but specifically about popular music. And it is hard to conclude that the music doesn't have to do any thing with a real life to be considered art, ( which is exactly what answer choice B is about) but rather it is about reality as it could be. And hence C has to be the answer...I believe