Why Was the "Civilization" of Native Americans Tragic

Why was the "civilization" of Native Americans tragic?

A) Some Native Americans refused to become civilized, so they were murdered by white Americans.
B) Many Native Americans tried to use civilized means like protests and boycotts to influence the U.S. government for their rights but failed.
C) Few Native Americans wanted to become "civilized" because it meant giving up their culture in exchange for land and citizenship.
D) Most Native Americans were unable to demonstrate aspects of civilization: literature, art, or organized society.
E) Some Native Americans sacrificed their culture to try to assimilate into white society and still they weren't accepted or granted rights.