Metals which can be extracted by smelting process is/are:
Correct answer: (b) (c) (d)
Solution: The process of extracting a metal from its oxide is known as 'smelting'. Most smelting processes involve direct reduction of the ore by carbon to metal and carbon dioxide. The production of primary aluminium is a good example of such a process. Metals include copper, nickel, lead, zinc, silver, cobalt, gold, cadmium, etc. Hence options A,B,C & D are correct.