"¿Cuáles son tus zapatos?"
Translation:Which shoes are yours?
Correct me if I'm wrong, but this sentence means "which are your shoes", right? So the answer "which is your footwear" is not a right solution since it is not plural, and shoes are not the same as footwear. Or if we accept approximate solutions like that, we could also accept answers like "which are the boots". But it is not an accident that we have dozens of different words for things we put on our feet, so why mix up these?