Respuesta :
The respective answers for all the four questions will be as follows,
1. A) A large increase in patriotic pride for preserving in a difficult war, and greater trusts in our government.
2. B) sit-ins at Columbia University.
3. A) They boycotted US products.
4. C) Increase trade and exchange between U.S. and China.
What caused the Vietnam War?
The United States had provided funding, armaments, and training to South Vietnam's government and military since Vietnam's partition into the communist North and the democratic South in 1954.
The Vietnam War was a long, costly and divisive conflict that pitted the communist government of North Vietnam against South Vietnam and its principal ally, the United States.
Learn more about Vietnam War here,
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