Answer:
Iron is the correct answer.
Step-by-step explanation:
The Hittites are known for developing the techniques for iron usage around 1500 BC. Earlier they were using Bronze. Bronze is harder than Iron, The Hittites started to Use Iron weapons which gave them an edge over its rivals and forming the Hittite empire. When the Hittite empire fell the iron smiths migrated to other places and disseminated the knowledge of ironwork. The Hittites were made up of several Indo-European speaking tribes. They occupied Anatolia in 17th century BC. They embarked on successful military campaigns due to the use of iron weapons and chariots.