In the electrolytic refining of a metal M, what would you take as the anode, the cathode, and electrolyte?
a) Anode: Metal M, Cathode: Inert electrode, Electrolyte: Metal salt solution
b) Anode: Inert electrode, Cathode: Metal M, Electrolyte: Metal salt solution
c) Anode: Metal M, Cathode: Metal M, Electrolyte: Metal salt solution
d) Anode: Metal M, Cathode: Metal M, Electrolyte: Water