In the commercial electrochemical process for aluminium extraction, the electrolyte used is
A. `Al(OH)_(3)`in NaOH solution
B. An aqueous solution of `Al_(2)(SO_(4))_(3)`
C. A molten mixture of `Al_(2)O_(3)and Na_(3)Alf_(6)`
D. A molten mixture of AlO (OH) and `Al(OH)_(3)`
