The correct option is C All of these
Before the Bronze Age, humans were dependent only on materials like- copper/stone & wood to make their weapons, utensils. Around 2300-3000 BC Bronze was discovered in some parts of Europe, middle east & China, Bronze was used to make weapons & other war tools which were much stronger than Stone or copper weapons. Therefore, by 1200 BC Bronze had replaced all other materials, Hence, Option D is correct.