Final answer:
The U.S. agreed to give up forts and land to the indigenous people as a result of Red Cloud's War.
Step-by-step explanation:
The answer is B: Red Cloud's War.
Red Cloud's War, which took place between 1866 and 1868, resulted in the Treaty of Fort Laramie in 1868, where the U.S. agreed to abandon forts and give up control of the Powder River Country in present-day Wyoming and Montana. This marked a rare instance where the U.S. agreed to cede land back to the indigenous people.
As a result of this treaty, the Native American tribes, including the Lakota Sioux, regained control over the Black Hills region, which was considered sacred to them.
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