The Domino Theory of the spread of communism led the United States to .

send American troops to fight in Vietnam

not enter the Vietnam War

enter WWII

send American troops to Korea

enter the Korean War

A.Send American Troops to fight in Viatnam

Explanation:

The perfect answer to this question would be "The United States president made the Truman Doctrine which encourage any countries under threat of Communism to be on his side"

The closes answer to that is A Hope it's Right

- three-quarters or two-thirds..

- "the constitution provides that an amendment may be proposed either by the congress with a two-thirds majority vote in both the house of representatives and the senate or by a constitutional convention called for by two-thirds of the state legislatures."

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