GKFix MCQ Question

What is the role of H2O in the reaction Cr2O7^2– + 3SO3^2– + 8H+ → 2Cr^3+ + 3SO4^2– + 4H2O?

• A. It acts as a catalyst
• B. It balances oxygen atoms
• C. It balances hydrogen atoms
• D. It acts as an oxidizing agent