Most of the american indian population was killed off by

Option A.

Explanation:

The Soviets declined to allow polls in Eastern European countries, is the right answer.

Relations between the Soviet Union and the United States following the Second World War were induced by a complicated interaction of political, ideological and economic causes, which led to variations between cautious assistance and oftentimes bitter superpower competition over the ages. The distinct discrepancies in the political arrangements of the two nations often stopped them from arriving a mutual agreement on key management matters. However, tensions between the two nations increased when the Soviets declined to concede polls in Eastern European countries.