What provided the primary unifying structure for south asian societies?

Which at first gave the south an edge in the civil war? a. a better-equipped army b. the invention of ironclad ships c. the drafting of slaves into the army

The persian wars started when emperor darius i began an invasion of greece. what caused darius to decide to attack greece? a. greek pirates had raided persia's merchant ships and coastal towns. b. greek armies had attacked and taken over land that belonged to persia. c. greek city-states had supported rebellions in the persian empire. d. greek leaders had declared independence from the persian empire.

How did china's location impact trade and its development?