The correct option is C Harappan culture
Harappan culture is recognized for advanced metallurgical techniques. Archaeologists have discovered usage of copper, bronze, tin, silver and gold. It was the first time that silver was extracted and used in Indus valley Civilisation. Its usage was mainly in the ornaments such as hair beads, necklace etc. Though it was also hammered to form thin sheets which could have been used to garnish eatables such as sweets.