Answer: play the four-trey, keep the nickel
Puzzle
Play the four-trey.
The double-four is already on the table. It is the highest four there is. Your four-ace cannot beat it. The four-ace is also a nickel — five points. Put it on this trick and West scores those five for free, on top of the one point for the trick.
The four-trey follows suit and loses the same way, without feeding them the count. Keep the four-ace for a later trick where the five might actually matter. Same habit as the earlier nickel puzzle: do not feed them five points on a trick they already own.
West asked for 30. Let this one go cheap. Your job is not to decorate their double.
This answers an earlier puzzle. Don't feed them the four-ace