The correct answer is answer B ("Choctaw").
Fort Towson was built to guard the southern border against colonial settlement. After confrontations begun, the Choctaw Nation relocated to the area of Doaksville, which became their economic capital. Fort Towson was positioned at the top of the Red River, granting easy access to navigable waters and protection for the natives.
The Choctaw ended up surrendering their territories to the Confederation in june of 1865.
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