Final answer:
The main difference between the social structure of the Inca compared to the Maya and Aztecs is the level of centralization and government control.
Step-by-step explanation:
The main difference between the social structure of the Inca in comparison to both the Maya and the Aztecs is the level of centralization and government control. While the Maya and Aztecs had hierarchical societies with rulers and a priestly class, the Inca Empire had a highly centralized government with absolute authority held by the Inca ruler. The Inca government provided all the goods and resources for the people, and there were no economic markets or money in their society.