Keeping your cool when someone’s trying to make you look bad is how you make them look bad instead.

When somebody is trying to provoke you, the reaction is the thing they need. Without it the attempt just sits there in the open with their name on it, visible to everyone watching. Staying level is not passivity, it is refusing to supply the missing piece. Everyone in the room can see what happened, and the only thing that would obscure it is you losing your temper.

Slow down and answer the question rather than the tone. If you have to say something, say it flatly. Leave the room if that is what level requires.