Explain how glutathione peroxidase converts hydrogen peroxide to water and the role of NADPH in this process.

• A. Glutathione peroxidase directly oxidizes hydrogen peroxide to water, and NADPH is used to stabilize the enzyme.
• B. Glutathione peroxidase uses NADPH to directly reduce hydrogen peroxide to water.
• C. Glutathione peroxidase uses glutathione to reduce hydrogen peroxide to water, and NADPH is needed to regenerate reduced glutathione.
• D. Glutathione peroxidase converts hydrogen peroxide to water by oxidizing NADPH.

Answer: (C)