Which Of These Things Is Not Like The Others

Remember on Sesame Street, "one of these kids is doing his own thing.."  and you had to pick out the one that was different?  Well here are pictures of our five chickens.  They were sexed and suppose to be all hens.  Can you pick out the one that I think, and have thought all along, is a rooster?  Mark still has hope that it's a hen, but "he" does not look like the others!