As an FA you will often come across passengers who simply don't care about the rules and regulations of flying. Talk to the interviewer about your method for dealing with these types of passengers.
"In my current FA role, I have been trained to handle uncooperative passengers in a variety of ways. If reasoning with them does not work then I will ask them to personally suggest what a reasonable solution may be. If they are unwilling to reason with me then I will remove myself from the situation asking another FA to step in."
"I've been trained to handle unruly passengers in a number of ways. Usually, these kinds of passengers don't respond well to people who try to exert authority onto them, so I explain to them that government regulations require passengers to be wearing their seat belts at this time, and that it was for the safety of all the passengers. I'd explain to him what would happen if he didn't have his seatbelt on during sudden turbulence. If he still refuses, then I'd emphasize the rules again and ask him what his suggestion is."