Answer: Codification
Explanation: Considering that the Hammurabi code was the oldest written law that contained 282 rules or laws that covered all aspects of the life of ancient Babylon, but also the entire empire, this meant codification. The significance of this codification, i.e. legal coverage throughout the empire, is that it was enacted during the rise of the Babylonian dynasty that ruled Mesopotamia.
Such codification systematically and legally regulated all important aspects of life in Mesopotamia during Babylonian rule. Namely, influencing crime reduction, regulating family relations and rights, marriage, divorce, rights over children, a sense of stability and order throughout the empire, everyone treated equally regardless of the nation in the empire, then all obligations around commercial contracts, payments, debts and regulation of commerce.