Answer:
The occupation of Alcatraz Island served as a strong symbol and uniting force for indigenous peoples everywhere because of the importance the island held in their ancestors' lives. Indians traveled to Alcatraz about 10,000 years before the Europeans even entered the Bay Area.
Explanation:
D. It allows citizens of many European countries to freely travel across the continent.
The exchange that most affected the indigenous people was the one of diseases. Native Americans hadn't encounter the diseases the European brought before, so they hadn't develop immunity to them. This is the major reason of the large death of Native Americans, besides the war between them and the brutality of the Europeans.