This is probably a joke but I'll answer anyway
By 'cheeks' they mean buttocks so by "making them clap" is referring to them being so big/thick that they clap or make noise when you walk or move around or something.
I probably got played lol but whatever
<span>D. Primitive man, because at ages ago we don't know how to cook and how to build a house, which we have in today's world and we are more civilised but at that time we used to live in caves and some time in open places near a fire to keep them warm so the can live and buck was also sleeping near a campfire so it looks like he was dreaming about the primitive man's who live in open near fire to stay warm and cook there prey.</span>