Answer:
Option: Ngo Dinh Diem
Explanation:
Before the Vietnam war, the United States was very much concern about the spread of Communism in Asia, as they gave it a term of Domino theory. The U.S. involvement in Vietnam began in 1954, though ongoing conflict in the region of North and South.
South Vietnam wanted to remain close ties with the West. Ngo Dinh Diem as a President in South Vietnam, it became possible for the U.S. to fight and overthrow Communism.
