ANS:C - both 'a' & 'b'

Both copper and zinc can be extracted from their ores by both pyrometallurgical and hydrometallurgical methods.

1. Copper: Copper can be extracted from its ores through pyrometallurgical methods such as smelting, where the ore is heated in a furnace with a reducing agent to produce crude copper, and hydrometallurgical methods such as leaching, where the ore is treated with a solvent to dissolve the copper minerals and then recovered through precipitation or solvent extraction.
2. Zinc: Zinc can also be extracted using both pyrometallurgical and hydrometallurgical methods. Pyrometallurgical methods include roasting of the ore followed by reduction with carbon to produce crude zinc, while hydrometallurgical methods involve leaching of the ore with sulfuric acid or ammonium chloride solution to dissolve the zinc minerals, followed by electrolysis or solvent extraction to recover the zinc metal.