单项选择题

TEXT C
American Indian Movement (AIM) is an organization devoted to promoting cultural awareness and political self-determination for Native Americans. AIM seeks recognition of treaty rights in accordance with agreements between Native American tribes and the United States government. The organization also supports Native American education and cultural programs. AIM is best known for its confrontational political demonstrations during the late 192s and 1970s.
AIM was founded in 1968 in Minneapolis, Minnesota, in response to complaints by Native American residents about police brutality. Members of the organization began to monitor police behavior. As the group gained strength, they also started to lobby for improved city services for the many Native Americans living in run-down tenant apartments, and they developed survival schools where Native American youths could be taught about their culture. Over the next four years, AIM expanded throughout the country, forming 40 chapters in cities and on reservations. AIM leaders, such as Dennis Banks and Russell Means, became well- known spokesmen for Native American rights.
AIM participated in a number of high-profile demonstrations from the late 192s through the late 1970s. From November 1969 to June 1971, AIM members participated in a 19-month occupation of Alcatraz Island, site of an abandoned federal prison in San Francisco Bay. The protest was intended to draw attention to the poor conditions of Native American reservations throughout the United States. The protesters proposed establishing a center for Native American studies on the island. Another group of Native Americans, allied with AIM, occupied a surplus military facility in Davis, California, beginning in October 194. These actions resulted in the establishment of Native American-controlled D-Q University in Davis in 1971. D-Q University is named for Deganawidah, an Iroquois prophet, and Quetzelcoatl, the Aztec god of peace and civilization.
AIM staged many demonstrations to protest the U.S. government’s treatment of Native Americans and the loss of their ancestral lands. In 1970 organization members participated in an occupation of a portion of Mount Rushmore National Monument in the Black Hills of South Dakota. Two years later, AIM members staged a Thanksgiving Day protest at Plymouth, Massachusetts, where the Pilgrims had landed in 1620, and briefly occupied a replica of the Pilgrim ship, the Mayflower.
AIM played a critical role in organizing the 1972 "Trail of Broken Treaties". Native American protesters converged on Washington, D.C., just before the presidential election in November. Marchers met with government officials at the Bureau of Indian Affairs (BIA. to present a 20-point program of demands. With police massed outside, marchers took over the BIA building and renamed it the "Native American Embassy". The occupation ended after authorities agreed to appoint a committee to study the demands and not to arrest the protesters.
The next major AIM action was the 1973 occupation of the town of Wounded Knee, the site of an infamous massacre of Native Americans by U.S. troops in 1890. Invited by tribal elders to protest a corrupt tribal government, AIM members and local allies took over the tiny hamlet. They were soon surrounded by agents from the Federal Bureau of Investigation (FBI), U.S. marshals, and the BIA police. The ensuing siege lasted for 70 days and ended in a standoff. A committee was appointed to examine the grievances that had led to the occupation, but no official action was ever taken.
AIM began to splinter apart. The organization’s national office closed in 1975, and all national officer positions were dissolved in 1979. Although AIM staged "The Longest Walk", a 1978 march from California to Washington, D)C), to protest bills introduced to the U.S. Congress that would reduce or abolish Native American treaty rights, the group foundered without national leadership. The 1990s have seen a modest revival of the organization. In 1992 local AIM chapters protested the celebrations marking the 500-year anniversary of Columbus’s first voyage to America. At a 1993 conference in New Mexico, 16 local AIM groups organized themselves as the Confederation of Autonomous AIM Chapters.
Why did AIM organize a number of demonstrations from the late 192s through the late 1970s