Which of the following best summarizes the reaction of American Indians to the flow of pioneer settlers into the western United States? *

A. American Indians avoided the pioneers. They did not want to have any contact with them.
B. American Indians were furious because of the wagon trains. They attacked as many pioneers as they could.
C. American Indians often met the settlers' wagon trains and traded with them. They rarely attacked the pioneers.
D. American Indian groups in the West demanded large payments from the pioneers in exchange for a safe journey.