Which of the following methods is used for refining impure metals?

Electrolytic refining is the method used for refining impure metals to obtain them in their purest form. In this setup, a thick block of the impure metal acts as the anode, while a thin strip of pure metal acts as the cathode. When electric current is passed through an electrolyte, the impure metal from the anode dissolves and deposits onto the cathode. The soluble impurities go into the solution, while the insoluble impurities settle down at the bottom of the anode and are known as anode mud.