Answer:
This is technically an opinion, but overall the answer should be
C. Development of astronomy
Explanation:
I would say C because B and D were nice, but didn't last past the fall of the Incas. Then you have A, again this was very good, and it might have influenced a few other civilization past the Incas, but overall, almost every country nowadays have a unique form of government. The answer is C because we still use most things that the Incas learnt about astronomy to this day all around the world.
May I have brainliest please? :)