This. Exactly this. There is no reason to say more. If you continue to get pestered in the interview regarding the “where else” topic, ask yourself if THIS place is truly the right place for you when they are more interested in their competition than they are of learning about you.
A seasoned AO/interviewer would unlikely broach this topic. But, don’t be fooled by your student tour guide trying to make friendly peer conversations when you let your guard down 