Which major or minor do you want for electronic music composition mixing and mastering?

I'd honestly recommend a buisness background. This may seem strange, but coming from someone with over 2 decades of musical background and a masters in music, music as a university course is a dead end. True ingenuity does not come from a classroom. Art by nature is subjective and therefore the true essence of music can never be touched upon by traditional classes. If you have talent, then you have talent. The trick isn't getting the credentials to justify it. You'll see plenty of successful artists with nothing but a high school diploma. The trick is marketing yourself well, getting connections and at least having a fall back plan if all goes to hell.