Which of the following electrolytes is used in electrolytic refining of copper?

The electrolyte used in the electrolytic refining of copper is CuSO4. The electrolyte is specifically an acidified solution of copper sulphate, which allows for the smooth flow of copper ions between electrodes. During electrolysis, a thick block of impure copper is made the anode, while a thin strip of pure copper is made the cathode. Impure copper from the anode dissolves into the solution and an equivalent amount of pure copper from the solution is deposited onto the cathode.