Begin by telling the interviewer that thankfully the majority of customers are pleasant to work with, and the rude customer situations are typically few and far between. Next, tell the interviewer that you understand customer service means always having a smile on your face, cheerful attitude, and pleasant demeanor. Tell the interviewer that you would continue interacting with the customer in a positive manner even when they were being challenging. Share that you never know what type of day that customer has had, and you smiling and being pleasant might be just what they need to help them turn their day around!