Fourth Answer
In the following position, dummy cashes the remaining spade winners.
Say that you discard two clubs. Partner discards the eight of diamonds and then the two of clubs; declarer discards the nine of clubs and then the three of diamonds. What’s going on in clubs? If the deuce had been partner’s only remaining club, partner probably wouldn’t have discarded it. Similarly, if declarer had a small club, declarer probably wouldn’t have discarded the nine. So it’s most likely that declarer and partner both started with three clubs, and each has one club remaining (partner has a small one, declarer has the King).
Now declarer thinks for a bit and then plays a heart to the Jack and your Queen.
What ‘s going on in hearts?