GKFix MCQ Question

Which of the following is a disproportionation reaction?

• A. Zn + Cu²⁺ → Zn²⁺ + Cu
• B. 2H₂ + O₂ → 2H₂O
• C. Cl₂ + H₂O → HCl + HOCl
• D. CaCO₃ → CaO + CO₂