Answer:
Option: A. HoChi Minh, ruler of North Vietnam, would take control of South Vietnam.
Step-by-step explanation:
US President Dwight Eisenhower developed the domino theory to describe Indochina politics in a news conference. The theory holds the idea if one country falls into communism, all neighboring nations will follow in. President Eisenhower applies this theory to explain the situation of Vietnam. If South Vietnam became a communist, then all its neighboring countries like Laos, Thailand, Burma, Cambodia, Malaysia, and Indonesia will turn toward it.