Using your imagination
Experienced players seldom try a spectacular opening lead; they are satisfied to produce leads that are consistently effective. Nevertheless, creativity is a valuable asset. Try using your imagination as South in these lead problems. Assume IMP scoring. My solutions include a conjectural deal that shows how the lead I suggest might gain. Since opening leads are not an exact science, I could as easily present a deal in which my suggested lead is disastrous.
Dummy will have balanced pattern with minimum opening values. A reasonable defensive plan considering your four trumps is to try to make declarer ruff repeatedly, forcing him to lose trump control so he can ‘t take his side-suit tricks. Your best chance to establish a forcing game is to lead your long suit. Try the 
J.
After a diamond lead and continuation, East can’t make his game.
West’s bid of 5
asked East to go on to slam if he had a control in clubs, the only unbid suit. Since East couldn’t oblige, North should have the 
K. Lead a low club.
A third-round club ruff will defeat the contract.
Lead the 3. Since East-West took only two rounds of bidding to reach game, they should have enough value to make it. You should put your faith in the club suit, but leading the queen may block the suit or blot out a significant singleton in your partner’s hand. On this deal, only the lead of a low club works. At matchpoint scoring, the lead of the queen would be defensible since to lead low might concede a vital overtrick. At IMPs, take your best chance for a set.
North has good diamonds, and not to lead a diamond would be masterminding; but for flexibility, lead the queen. If you retain the lead, you may be able to shift effectively through dummy.
North will drop the J under your queen as a suit-preference signal, and your switch to the 
J will work well.