Why were native americans moved to smaller and smaller reservation in the 1850s?

The U.S. government forced the Native Americans to move to reservations in exchange for protection from attacks by white settlers. In addition, the Indians were supposed to be given a yearly payment that would include money in addition to food, livestock, household goods and farming tools. So basically white people were greedy for their land.

Option A.

Explanation:

white settlers discovered gold and silver in land already set aside for native Americans , is the right answer.

In the 1850's, the White Settlers in America introduced a new reservation system for the Native Americans, this system is known as the Indian reservation system. With the introduction of this system, the White Settlers could live on the lands of the  Native Americans. The main reason for establishing such a system was that the White Settlers found gold in the areas inhabited by the Native American population.

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