Which of the following occurred after the Vietnam war spread into Vietnam but before Vietnam was united under a communist government?

A. Ho Chi Minh took leadership of the Vietcong.
B. Richard Nixon resigned from office after the Watergate scandal.
C. The Khmer Rouge group invaded Vietnam.
D. A cease-fire allowed U.S. troops to leave Vietnam.

i think its A

or b

To determine which event occurred after the Vietnam War spread into Vietnam but before Vietnam was united under a communist government, let's analyze the given options:

A. Ho Chi Minh took leadership of the Vietcong: To figure out if this happened before Vietnam was united under a communist government, we need to understand that Ho Chi Minh was actually the leader of the Democratic Republic of Vietnam, which was later renamed North Vietnam. This suggests that Ho Chi Minh's involvement would likely have occurred during the war or before it spread into Vietnam, rather than after Vietnam was united under a communist government.

B. Richard Nixon resigned from office after the Watergate scandal: This event is unrelated to the situation in Vietnam and therefore can be eliminated as a potential answer.

C. The Khmer Rouge group invaded Vietnam: The Khmer Rouge group was a Cambodian communist organization responsible for the Cambodian genocide. While they were active during the same time period as the Vietnam War, which lasted from 1955 to 1975, their invasion of Vietnam did not happen after the war spread into Vietnam.

D. A cease-fire allowed U.S. troops to leave Vietnam: This option is referring to the Paris Peace Accords of 1973, which led to a ceasefire between the United States and North Vietnam. The agreement allowed the withdrawal of U.S. forces from Vietnam, suggesting that this event did occur after the war spread into Vietnam but before the country was united under a communist government.

Based on the analysis, the correct answer is option D: A cease-fire allowed U.S. troops to leave Vietnam.