Final answer:
The violent Native American resistance in the Black Hills was precipitated by the U.S. government's disregard for the Treaty of Fort Laramie, failure to prevent settler encroachment, and the military enforcement of land seizures following the discovery of gold.
Step-by-step explanation:
Direct Cause of Native American Resistance in the Black Hills
The most direct cause of the violent resistance by Native American tribes against white settlers in the region of the Black Hills was directly related to the discovery of gold and the refusal of the U.S. government to honor existing treaties. After gold was found, settlers with the support of U.S. cavalry troops began to flood the area. Although the government offered to lease or buy the Black Hills, when the Native American tribes refused, the U.S. government imposed a price, ordered the tribes to move, and prepared to enforce this arrangement by military means. This clear disregard for sovereign rights and treaties is embodied in option 1: President Grant would no longer honor the Treaty of Fort Laramie that kept white settlers off their land.