The correct answer is: "The Dawes Act broke up lands into smaller plots for individuals, but earlier acts gave larger tracts to entire tribes".
The Dawes Act was enacted by the US Congress in 1891. It divided tribal lands in individual allotments that would be granted individually to American Indians. The ones who got those pieces of land and accepted to live apart from the tribe, would be granted the US citizenship.
The main objective of this act was to end communal forms of ownership exercised by the tribes, that were previously allowed, and progressively assimilate the Indian population into the US society and way of life.