What was the main purpose of NATO

(A.) Overthrew the Soviet Union

(B.) create a European economic union

(C.) deter the Soviet Union from aggression

(D.) rebuild Europe

(C.) deter the Soviet Union from aggression.

Explanation:

NATO was formed in 1949, just 4 years after the end of WWII. Large units of the Red Army were stationing in the countries of Eastern Europe and there were serious conflicts and disagreements between the West and the Soviet Union, particularly over the future of Germany. That significant military presence instilled fears of a Soviet invasion in Western Europe to spread communism. In 1948, the Soviet military had blocked Berlin in order to cut communication lines between the Western part of the city and the Allies.

So, in this climate of confrontations and fears of Soviet aggression, the United States and its European allies got together to create NATO.