A total of 21 cards, consisting of 4 kings, 4 queens, 4 jacks, 4 tens, 4 nines, and 1 joker were dealt to Art, Ben, and Cal. The cards were dealt evenly: 7 per player. Then all jacks, tens, and nines were discarded.

At that point:

1. The combined hands consisted of 4 kings, 4 queens, and 1 joker.
2. Art had 2 cards, Ben had 3 cards, and Cal had 4 cards.
3. The man with the most singletons did not have the joker.
4. No man had more than 2 kings.

Who had the joker?