Final answer:
With the storming of the Presidential Palace, the Communists took over South Vietnam in April 1975. The South Vietnamese and their American allies were evacuated, and when the South Vietnamese flag was lowered, the refugees felt defeated and sad.
Step-by-step explanation:
The event that leads to the Communists taking over South Vietnam is the storming of the Presidential Palace. The U.S conducted several operations to evacuate children and persons who supported them from South Vietnam. On April 29, 1975, the North Vietnamese and Viet Cong forces moved through the outskirts of Saigon. The South surrendered the following day when North Vietnamese forces entered Saigon. Refugees felt defeated and sad as they witnessed the lowering of the South Vietnamese flag, symbolizing the victory of the Communist forces and the end of their homeland as they knew it.
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