What was the name given to the idea that if vietnam fell to communism, the rest of southeast asia would become communist?
a. the domino theory
b. the communist theory
c. the roll back theory
d. the steamroller theory

Option A. The domino theory. This theory was based in the belief that communism could spread from Sout Vietnam through all the South East of Asia. The analogy was that China's Comumunism was the first domino piece that, after which Korea fell, and it would follow with Vietnam, Laos, Cambodia, Thailand, Malasy, Indonesia, Burma and India.