How Did the Aryan Level of Social Integration Compare to That

How did the Aryan level of social integration compare to that of Harappan civilization?

A) The Aryans offered a more centralized tradition of absolute statehood.
B) The Aryans were less warlike and thus depended more on a priesthood than the Harappans.
C) The Aryans failed to surpass the level of tribal organization and remained nomadic pastoralists.
D) The Aryans had a less centralized tradition of tribal organization and then later created small kingdoms.