Clubs are trumps and South to lead,
North/South to take 3/5 tricks
This one has some really tricky ideas!
The first is the idea of North being able to overtake the 5C with the 6. This is because from the position you need the lead coming from the North hand through East’s honours so that they are finessed! If South leads, they are leading into East’s strength and letting them score.
It’s also not too often that you don’t want to win tricks. With this one here, ducking club tricks really comes into play. This is the sacrifice of instant satisfaction for a long term gain of an extra trick. If you don’t duck clubs you are endplayed. This means that you must lead and give the East hand 2 tricks.