Chess.com's Chess Mentor is like that. It asks you to pick a move. And for every incorrect choice it has at least a little to say about why it's not the solution move... sometimes more than a little if it was a good try. It has a lot of different positions.
You can also do this on your own with a collection of annotated games or with software although in both cases you either wont have the chance to explore every move, or won't be given a verbal explanation of why and why not for every move.
That would be just awesome!!! Positional trainer like u guess the best developing move and and stuff now that would be worth getting a menbership!!