The correct answer is B) Vietnam was not able to hold democratic elections because the United States would not allow them.
The statement that is true is "Vietnam was not able to hold democratic elections because the United States would not allow them."
During the Cold War years, the Soviet Union was decided to spread Communism in many different countries of the world. He has done that in China, in North Korea, and on the island of Cuba with leader Fidel Castro. The United States tried to stop the spread of Communism and was decided to do everything to stop it in Vietnam. That is why the US supported the government of South Vietnam and even sent troops.