Which sentence from "american indian civil rights” best describes the conflict the author develops in the text?

most experts agree that is was over ten thousand years ago, well before european settlers began exploring this region of the world.
relationships between the europeans and american indians turned hostile, and rights were one by one stripped away from american indians.
one of the most sweeping blows to the american indian community occurred in 1830 when president andrew jackson signed the indian removal act.
over the years, american indian activists have valiantly fought for reform and for the government to honor certain treaty obligations.