The diagram illustrates the apparatus used to obtain aluminium from aluminium oxide. Which statement about this process is correct?
- AThe electrolyte is a solid mixture of aluminium oxide and cryolite.
- BThe electrolyte is aluminium oxide dissolved in water.
- CThe equation for the reaction at the positive electrode is $\text{Al}^{3+} + 3\text{e}^- \rightarrow \text{Al}$.
- DThe positive carbon electrodes lose mass during the process and need regular replacement.