See that is a good question and will make potential teachers really think about what they'd do. This is a very thought out question that is sure to help separate the good from the great future teaching candidates. What you should do in stressful situations as a teacher though is calm down for a while, take a deep breath, and remember what has worked for you in the past and go off that (even if you have limited teaching experience) since you can build on it and make a plan to handle that specific situation in the classroom.