Electrolysis is carried out on aqueous copper(II) sulfate using copper electrodes. What equation represents the reaction at the anode?
- A$\text{Cu} \rightarrow \text{Cu}^{2+} + 2e^-$
- B$\text{Cu}^{2+} + 2e^- \rightarrow \text{Cu}$
- C$4\text{OH}^- \rightarrow \text{O}_2 + 2\text{H}_2\text{O} + 4e^-$
- D$2\text{SO}_4^{2-} + 2\text{H}_2\text{O} \rightarrow 2\text{H}_2\text{SO}_4 + \text{O}_2 + 4e^-$