Yes, we can answer it and we have, but Catholics reject the answer and then do a victory lap claiming we can’t answer it.
If you can answer it then please do. Either the Church is infallible in both determining the canon of Bible and in preaching the faith, or it is not infallible in either. You cannot claim that the Church is infallible in determining what is Scripture but not in teaching the faith. The former is only a subset of the latter.
I have a question for you: do the Deuterocanonical / Apocryphal books belong in the Bible? And who gets to decide?