Here is your hand:
Your right hand opponent opens the bidding one heart in second seat. You pass, and left hand opponent responds one spade. Right hand opponents’s rebid is two clubs, and left hand opponent jumps to four hearts. Here is summary of the auction:
You lead the deuce of spades and see this dummy:
Dummy plays low, your partner plays the king, and declarer wins the ace.
Now declarer draws trumps ending in hand, your partner having shown up with four small hearts.
Declarer cashes the jack of spades and leads the 10 to dummy’s queen. Declarer cashes dummy’s remaining two spades. What do you discard on that last spade?
Hold onto those clubs for dear life! Remember the bidding. If you pitch a club, declarer is going to drop your queen for an overtrick.