In teaching and in life, people sometimes face difficult situations about whether to intervene in a conflict between people, such as students or other teachers. Concerns about how one will be perceived, fear of personal danger, or sometimes even ambiguity about whether it is better to let the parties resolve the conflict themselves all can make the decision about whether to intervene a challenging one. Describe a situation in which you faced such a decision about whether to intervene, and explain how you handled the situation.
Of course, any answers that we give on this site will be based on our own personal experiences and these will not be the same as your experiences. Therefore, what I will do here is to give a couple of examples from my own life and try to suggest ways in which you might answer this question from your own experiences.
The best way to answer this question is to think about the different contexts in which you might run into conflicts between people you know. One of these contexts is within your own family. Another is between friends. You might have siblings who are in conflict with one another. You might have friends who come into conflict as well. One example in my own life that was a combination of these was when my younger brother and his wife were thinking about getting divorced. She was a friend and, of course, a relative of sorts. I had to decide whether to try to patch things up between them. I was worried that A) I would make things worse and/or B) that I would be seen as meddling. I think I made the wrong choice because I tried to patch things up and failed, straining my relationship with my brother in the process.
Another context is at work. Since you mention teaching, I will say that you will tend to have students who come in conflict with one another. Here, you have to be careful to make sure you are not perceived as taking sides. I have tended to simply try to listen to both sides of conflicts and try to nudge people towards reconciliation. It does not always work, but I think this is the best approach.