The interviewer wants to hear that customers are your priority. Tell the interviewer that you would graciously stop what you were doing and start by genuinely listening to the customer. Next, share that you would apologize to the customer and take whatever corrective action was necessary. Be sure to mention that most challenging customers really do not take much time, and they really just want to know that their opinion is being heard. Finally, be sure to mention that once you have the customer on their way you would go back to working on your task.