The Great Plains and Mountain Frontier Comprised a Complex Web

The Great Plains and mountain frontier comprised a complex web of cultures and environments in which Spanish, Anglo-American, and Indian cultures penetrated one another and often produced swift change. An excellent example of this change was

A) the voluntary adoption of the Catholic faith by Native Americans.
B) the use of buffalo robe camouflage by Anglo hunters.
C) western settlers using Indian trails to find their way across the "trackless wilderness" of the western Great Plains.
D) the shift from village-centered agriculture to nomadic hunter by the Plains Indians.