Correct Answer: cathode

Solution : The correct answer is the cathode.

The anode is the impure metal to be refined in electrolytic refining, whereas the cathode is a thin strip of high-purity metal. The solution uses metal salt as the electrolyte. When an electric current passes through the electrolyte, pure metal from the anode dissolves, and deposits to form a cathode. Insoluble impurities settle to the anode's bottom and generate anode mud. The soluble impurities are re-incorporated into the mixture.