Concept:Galvanized iron is coated with zinc to prevent rusting. When oil touches this zinc coating, harmful chemical reactions occur.Explanation:Zinc reacts with components of the oil to form toxic zinc compounds. This makes the oil unsafe to eat. The oil’s quality also drops because chemical changes cause rancidity and spoil the taste and smell.Additionally, moisture or acidic impurities in the oil slowly corrode the zinc layer. This exposes the iron underneath to rust.Options A, B, and C each describe one valid reason. Since all three effects happen together, the complete answer includes all of them.Answer:D. All of above