When an aqueous solution containing copper(II) nitrate and silver nitrate is electrolysed using pure copper electrodes, which half-equation shows the process taking place at the anode?
- A$\text{Cu} \rightarrow \text{Cu}^{2+} + 2e^{-}$
- B$\text{Cu}^{2+} + 2e^{-} \rightarrow \text{Cu}$
- C$\text{Ag} \rightarrow \text{Ag}^{+} + e^{-}$
- D$\text{Ag}^{+} + e^{-} \rightarrow \text{Ag}$