The answer is D. popping popcorn,  all three are just examples of physical change due to shredding, breaking and cutting that change only the size of the material while in popping popcorn it undergoes a chemical change wherein the components of the corn produces new product it is evident by the change in color and hardness of corn and this change is not reversible or you cannot change it back to its original material
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D. popping popcorn........ cornpop
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