During the electrolysis of $\text{CuSO}_4\text{(aq)}$, what ionic equation represents the reaction occurring at the cathode?
- A$\text{Cu} + 2e^- \rightarrow \text{Cu}^{2+}$
- B$\text{Cu}^{2+} + 2e^- \rightarrow \text{Cu}$
- C$2\text{H}_2\text{O} + \text{Cu}^{2+} + 2e^- \rightarrow \text{Cu(OH)}_2 + \text{O}_2$
- D$\text{SO}_4^{2-} + 4\text{H}^+ + 2e^- \rightarrow \text{H}_2\text{SO}_4 + \text{H}_2$