Other than the ♠QJ, the only high card that West can have is the ♦Q, as Declarer needs everything else to make up his 1NT bid.  So Declarer has the ♣A and therefore three Club tricks … and he has four more tricks in the major suits.  He needs two tricks from Diamonds and, sure enough, at Trick 3 he leads a Diamond to his Ten and West’s Queen.  A Spade knocks out Declarer’s Ace, and then a Diamond knocks out your Ace.  But, alas, you are out of Spades and Declarer is one with 9 tricks.  Well, that was how the play went when the deal was actually played, but we know you did better, didn’t you?

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