GKFix MCQ Question

Which example illustrates formation of lower oxidation state with excess reductant?

• A. Cl₂ oxidizing Fe²⁺ to Fe³⁺
• B. S burning in air gives SO₂
• C. Excess H₂ reduces CuO to Cu
• D. Sn²⁺ reducing Fe³⁺ to Fe²⁺ when in excess