If a person with a severe peanut allergy accidentally consumes peanuts, which consequence explains widespread vasodilation during anaphylaxis?

💡 Explanation

During anaphylaxis, mast cell degranulation releases histamine and other mediators. Because histamine binds to endothelial cells, it triggers vasodilation, leading to a drop in blood pressure and shock. Therefore, mast cell degranulation is the correct answer, rather than complement, T-cell, or B-cell-mediated mechanisms.

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