Electrolytic reduction cell used for conversion of calcined Al2O3 to Al is a carbon lined furnace operating at 800-900 °C. The purpose of electric current supplied to the furnace is to

A. Achieve very high purity of aluminium (99.9%)

B. Keep the electrolyte in liquid condition by the generation of heat

C. Electrolytically dissociate alumina

D. Both (B) & (C)

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