Respuesta :
The United States Began increasing its sincerity of troops to the war in Vietnam, in 1965.
What did the US do in the Vietnam War?
In 1965, The United States move to Vietnam with the principal intention of forbidding a communist takeover of the region.
In March 1965, president Johnson establishes a three-year political campaign of free-burning attacks of targets in North Vietnam.
In the same month, U.S. Marines landed on formations near Da Nang, South Vietnam, as the first American battle troops to enter Vietnam and Began increasing its seriousness of forces to the war in Vietnam.
Therefore, option C is correct.
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