The Respective Standard Oxidation Potentials for Cu -Cu²⁺, Ni -Ni²⁺

Multiple Choice

The respective standard oxidation potentials for Cu -Cu²⁺, Ni -Ni²⁺, and Ag -Ag⁺ are (in V)
- 0) 34, +0.28, and - 0.80. Impure copper slabs at the anode are refined electrochemically, affording much purer metallic copper at the cathode. Which statement below is true?

A) Ni is oxidized preferentially over Cu, and Ni²⁺ is reduced much less readily than Cu²⁺, so Ni is separated as Ni²⁺ in the electrolyte solution.
B) Cu is oxidized preferentially over both Ni and Ag, so both Ni and Ag metals are separated as sludges below the anode.
C) Ag is oxidized preferentially over Cu, and Ag⁺ is reduced much less readily than Cu²⁺, so Ag is separated as Ag⁺ in the electrolyte solution.
D) Ag is oxidized preferentially over Cu, and Ag⁺ is reduced much more readily than Cu²⁺, so Ag plates out with Cu at the cathode and cannot readily be removed from impure copper.
E) Both Ni and Ag are oxidized preferentially over Cu and Ni²⁺, and Ag⁺ is reduced much less readily than Cu²⁺, so Ni and Ag are separated as Ni²⁺ and Ag⁺ in the electrolyte solution.