Answer:
Option: C. Stated if Vietnam fell to the Communists, then the rest of Asia would become Communist.
Step-by-step 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 domino theory was a theory raised extensively in the 1960s. The plan stated if one nation came under communism, then the surrounding countries would become communist. The Domino effect came as a foreign policy during the Presidency of Kennedy and Johnson to support America's military involvement in the Vietnam War.