Vous can refer to a group of people (2nd person plural) or refer to a single person (formal address, 2nd person singular). The agreement of the participle reflects this, being either plural or singular, depending on how many people you are addressing.

Bonjour John,

On the face of it, I agree that for the second-person plural; the conjugation should be Vous vous êtes cachés ......

So without sight of the actual quiz question, I note that you wrote "I conjugated it as Vous êtes cachés" and this is indeed incorrect without the reflexive vous included.

Bonne journée

Jim

Hi John, I wondered the same when I came across the same quiz. There was no way to tell if the *vous* means one person or more than two.

I guess usually a wardrobe cannot house many people... so it must be the single polite *vous*? It is not a good sample sentence to use as the quiz...