Trick 7		North
Declarer (W) ♠ - A 10 9 8 6 ♥ - A 10 5 ♦ - A K 3 ♣ - A 3	> ?			Dummy (E) ♠ - K Q J 7 3 ♥ - K J 3 ♦ - Q J 10 ♣ - 9 2
		South		Won = 6 Lost = 0

Declarer draws Opponents' trumps in two rounds, then plays three rounds of ♦s.
This is the situation at trick 7.   What should Declarer lead ?