I'm not a UFC fighter, but for me I think it would be a straight armbar. An opponent landed one on me in a judo match, and even though he let go as soon as I tapped (which was instantly because of how quickly he put it on), my arm still hurt for several days afterward. If you get choked out, fine; if you get hit in the face, great. But if you mess up a joint, that's going to be with you for a long, long time.