GKFix MCQ Question

Which of the following illustrates that excess reducing agent forms lower oxidation state?

• A. S burned in air gives SO3
• B. Fe³⁺ reduced to Fe²⁺ by Sn²⁺ in excess
• C. CH4 oxidized by excess O2 to CO2
• D. KMnO4 reduced to MnO2 in basic medium