A: providing allotments of land.
The Dawes Act, also known as the General Allotment Act, authorized the President of the United States to survey Native American tribal land and divide it into allotments for individual Native Americans. Those who accepted the allotments and lived separately from the tribe would be granted United States citizenship.
The objectives of this Act were to abolish tribal and communal land ownership of the tribes into individual land ownership rigths in order to transfer lands under Native American control to white settlers and stimulate assimilation of them into mainstream American society., and thereby lift individual Native Americans out of poverty.
It enabled civilizations around rivers to emerge because it enabled them to grow their own food in fertile lands. It also enabled class division to emerge into those who dealt with trade and those grew food. It also enabled rise of political system like monarchies with rulers and dynasties.
Traps of crossbows poised to fire on the intruders is the answer