Which Cold War policy led America to send troops to Vietnam?   Group of answer choicesMarshall PlanEisenhower DoctrineIsolationismDomino Theory

The Cold War policy that led America to send troops to Vietnam is the Domino Theory.

Explanation:

1. Domino Theory: This was the idea that if one country in a region fell to communism, neighboring countries would also fall, like a row of dominos. This theory was particularly influential in the context of Southeast Asia during the Cold War, as American leaders feared that the spread of communism in Vietnam would lead to a chain reaction in other countries in the region.

2. Marshall Plan: This policy was primarily focused on the economic recovery of Europe after World War II and did not directly relate to military involvement in Vietnam.

3. Eisenhower Doctrine: While this doctrine did address the Middle East and the containment of communism, it was not the primary reason for U.S. military involvement in Vietnam.

4. Isolationism: This was a foreign policy approach that suggests avoiding alliances and wars; thus, it contradicts the action of sending troops to Vietnam.

In summary, the Domino Theory was the key policy influencing American engagement in Vietnam, as U.S. leaders believed it was necessary to prevent the fall of Vietnam to communism to avoid a broader regional impact.