Answer: The correct answer is C. The invasion of South Korea by Communist forces
Explanation:
The invasion of South Korea by Communist forces first tested the U.S. policy of containment in Asia.
The US adopted containment as its Cold War Policy to prevent communism to spread after the end of World War II.
South Korea was forcefully taken over by the communist forces that tested the U.S. policy of containment in Asia at first.
Therefore the correct option is C.
Learn more about the US policy of containment here:
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