Anode oxidation with copper electrodes

Steps:

• Anode undergoes oxidation during electrolysis.
• Copper electrodes in Cu²⁺ solution mean anode dissolves as Cu atoms oxidize.
• Cu loses 2 electrons to form Cu²⁺ ions, maintaining solution concentration.
• Reaction equation is Cu → Cu²⁺ + 2e⁻.

Why A is correct:

• Represents oxidation of copper anode, per standard electrolysis rules for reactive electrodes.

Why the others are wrong:

• B: Cathode reduction depositing Cu.
• C: Oxygen evolution at inert anode in aqueous solution.
• D: Non-standard sulfate oxidation not occurring here.

Final answer: A