What main demand of native american advocacy groups did the passage of the indian self-determination act of 1975 meet?

Self-rule: American Indian groups in the 1970s demanded self-rule of the reservations. This act gave them that right.

The American Indian groups and in particular AIM wanted to rule reservations themselves and get rid of the federal government in their affairs. They used militant means and occupied locations and towns to get the US to surrender their power over the reservations. The Indian Self-Determination Act gave reservations control over their land, government, and culture.