Answer : The correct option is, (a) anode
Explanation :
As we know that there are two types of cell which are, electrolytic cell and electrochemical cell or galvanic cell.
Electrolytic cell : It is defined as the cell in which the chemical reaction occurs by passing of the current from external source.
In the electrolytic cell, the oxidation occurs at anode which is a positive electrode and reduction occurs at cathode which is a negative electrode.
For example : On passing electricity in the molten NaCl, Na and chlorine gas are obtained at cathode and anode respectively.
Electrochemical cell : It is defined as the cell in which the chemical reaction occurs with the production of electric potential difference between the two electrodes.
In this cell, the oxidation occurs at anode which is a negative electrode and reduction occurs at cathode which is a positive electrode.
Hence, in an electrolytic cell, the oxidation occur at an anode.