The interviewer wants to hear that you work through stressful situations with ease not allowing the situation to get the best of you. Think back to a past stressful situation. Share an overview of what occurred, and explain why it was so stressful. Be sure to mention that even though it was stressful, you maintained your professional, positive attitude and did not allow it to get the best of you. Share what you did to get through that situation, and mention what you learned from that stressful time.