Use the STAR technique - Situation, Action, Task, Result. Pick a time and tell a story that demonstrates your ability to deal with someone who is upset. How do you handle yourself?
When working with the public, unexpected problems or issues inevitably arise. Please tell me about a time when you were in a situation where you had to deal with a customer's or person's complaint. How did you handle the situation? What was the result?
Assessing your conflict resolution skills, and your relationship management.