Concept:A physical change alters form or state without changing chemical composition.Explanation:Option A: Exposing white phosphorus to air causes oxidation/combustion — chemical change.Option B: Burning kerosene involves combustion, producing new substances — chemical change.Option C: Dissolving calcium in water forms calcium hydroxide and hydrogen gas — chemical change.Option D: Freezing ice cream only changes its state from liquid to solid — no new substance is formed, so it is a physical change.Answer:D. Freezing ice cream