Veronica Sawyer: This may seem like a really stupid question... J.D.: There are no stupid questions. Veronica Sawyer: You inherit 5 million dollars the same day aliens land on the earth and say they're going to blow it up in 2 days. What do you do? J.D.: That's the stupidest question I've ever heard.
But anyway, I think they'd listen to dubstep. It's techy and somewhat futuristic. It's also a bit hardcore and would serve as appropriate background music as they destroy the planet. Furthermore, because most dubstep sounds like farts being tuned to ridiculous atonal pitches, it'd suit their heightened understanding of music, as they do not share our human need for music to make melodic sense.
Now how do y'all know aliens are so futuristic. What if they're some dirty savages that have no technology?
I think it's just a natural assumption. It seems somewhat unlikely that "dirty savages" who have no technology would have the capability to navigate the galaxy and travel to Earth.