NATO was formed with the motive to safeguard countries against Soviet Union and spread of communism and US also join NATO with the same motive.
<h3 /><h3>When did US join NATO?</h3>
NATO(North Atlantic Treaty Organization) was formed in 1949 by the United States and several European nations to safeguard themselves against the USSR.
It was the first peace military alliance US entered outside the Western region.United States join the NATO or rather it was formed in 1949 to provide protection against the Soviet Union and to check the communism spread.
Therefore, option b aptly describes the motive of US to join NATO.
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