When a simple question makes someone furious, the question usually hit something real.

Disproportion is the signal worth reading. A plain question deserves a plain answer, and when the response is anger instead, the heat is usually coming from something the question brushed against rather than from the question itself. That does not automatically make you right, but it does tell you where the sore place is.

Notice the reaction without escalating to match it. Let the silence sit rather than filling it with apology or a second question. And turn the same instrument on yourself, because the subjects that make you flare up are pointing at something you have not looked at.