Which sentence best summarizes the system of government that Darius I introduced in the Persian Empire?

A.
He split the empire into provinces headed by local leaders, but he kept the military under his control.
B.
He divided the empire into independent kingdoms whose kings had to pay a yearly fee to him.
C.
He created councils to rule over towns and villages and ruled the council leaders from his capital.
D.
He created a single, central, governing body whose decisions were applied throughout the empire.