NORTH  KQ32  AT82  AQ4  93  8  J75  J97652  QJ5    AT6  K93  T3  T8642    J9754  Q64  K8  AK7

Dealer: South    Vul: Both   MP Scoring West Pass Pass North 2N1 Pass East Pass Pass South 1 42

How do you eke out a twelfth trick?

Clubs were led and repeated after trumps were started and immediately halted by defender's A.

What next?
There seemed to be 4 plans:
1) A to drop the singleton K on either side. Computing...
Requires a 5:1 division of outstanding hearts, the 1 side being that singleton.
5-1 occurs 14.5% of the time and any particular card being the 1 occurs (1of 6 total times ) 16.7% of those times. About 2.4%
2) The Chinese finesse: The Q is led from hand hoping that the K is onside, not singleton, and the defender plays low, hoping to capture the upcoming hidden J, thus, 25% of the time, requiring misdefence.
3) Leading towards the Q early in the hand before other suits are known hoping for either misdefence OR East to hold the K and not the J and choose to play low
4) Leading towards dummy's T, hoping for KJx(x) onside and a low play.

How does one weigh the probabilities here?
Do you study your opponents and rate each one on where in their lessons they might be?
Do you play one way against one opponent and another another? Don't you? Sometimes no? Sometimes not?