The most unexpected and delightful #1 pop single of the year comes from a hip-hop duo I’ve never much cottoned to, along with a mentor I’ve never much cottoned to. But Rae Sremmurd are undoubtedly the sound of young America right now, and on “Black Beatles” they go for broke, telling you that they know they’re rock stars, and dare you to prove otherwise. Producer Mike WiLL Made-It might’ve given them his sickest beat ever (or at least in many years), and they know exactly what to do with it. Gucci Mane does too, but he’s been doing this for years; his drop-in verse has the feel of the wise old uncle stopping by the house. If, that is, said uncle stopped by to tell you about “a yellow bitch with green hair, a real weirdo. Sure, this might’ve gotten to #1 on the back of the “Mannequin Challenge,” but it’s stayed there on its own merits.