Which of the following best describes the Domino Theory?

A.)American politicians used this principle to limit the number of combat troops that were
committed to the defense of South Vietnam.

B.)It was used as justification for U. S. intervention in Southeast Asia, to prevent democratic nations
from falling to communist insurgencies.

C.)President Kennedy campaigned in 1963 by promising to replace the domino theory as a principle
for foreign policy.

D.)After 1963, the U. S. commitment to defend nations like Vietnam declined, as an economic
recession took hold across the nation.