Yeah I guess this is just random selection I only use dogecoin out of those four coins.
No 
they are not randomly assigned , I hope you have a lot of alts here Forum is now using Advanced AI to find Alts , read quote below this:just randomly assigned then?
It's using advanced AI to find all of your alt accounts and give you the correct badges.
anyways I never heard those three coins except doge and never discuss it on altcoin section since I'm not totally fan of alts.