The American attitude shifted in favor of rights for Native Americans. This is based on "Polls showed that Americans believed in rights for Native Americans". Why it's not B is because it wasn't the polling that contributed to the act, but what the polls showed which is C.
The best option is would be to prevent future acts of terrorism in the United States through coordination. It is the most important transformation of the US government by largely transforming and realigning government activities into a single department where the primary goal is to protect the United States of America.
The answer is c, an alliance is the formal name
