Aluminium metal is obtained from aluminium oxide through electrolysis. Which ionic half-equation shows a reaction occurring at the electrode named?
- A$2\text{O}^{2-} \rightarrow \text{O}_2 + 2e^-$ at the anode
- B$\text{Al}^{3+} + 3e^- \rightarrow \text{Al}$ at the anode
- C$2\text{O}^{2-} \rightarrow \text{O}_2 + 4e^-$ at the cathode
- D$\text{Al}^{3+} + 3e^- \rightarrow \text{Al}$ at the cathode