What's the right level of control users should have over their data?
Then as a follow up I would ask what's keeping Facebook from implementing those controls.
Unless this was already covered in an acceptable way after the Cambridge Analytica f*ckup (I haven't followed what actions Facebook took afterwards to address the issue), I would also ask about what are they doing about policing bad actors, companies trawling or leaking users' private information or abusing it. How are they going to better prevent that in the future. Once it's outside of Facebook they've already lost control of the situation.