What was the name of the theory that said that if one country in a region fell to Communism, others would surely follow?

domino theory

arms race

brinkmanship

containment theory

O

the domino theory! <3

The right answer is: domino theory.

Explanation:

The domino theory was seen as a likely outcome in the geopolitical chess of the Cold War in the developing world. According to the views and mentality of the era, if one country falls to Communist hands, neighbors will follow. It was a rationale for action in both Korea and Vietnam. It was also applied to Latin America.