To review, a double question offers a defined range of options, of which one is the true or most likely answer. Since I imagine you’re pros a asking double questions by now, here’s a triple question.
He asks whether the axes are Caesar’s or Cicero’s or Cato’s: quaesit an Caesāris an Cicerōnis an Catōnis secūrēs sunt.
To answer double or triple questions, the respondent had best echo the grammar of the question.
The are Cato’s: Catōnis [sunt].
Here’s another:
Did you see the boar itself, or merely smell its stench: vidistīne verrem ipsum an mōdō eius afflātum olfēcistī?
I just caught a whiff: mōdō olfēcī.
The Essential AG: 337
Latin for Addicts 