The first alternative is correct (A).
A war is a terroir scenario, where the soldiers go through very difficult times. Many lose friends, see the suffering of people, children, anyway. That way, no matter how psychologically strong a soldier is, his emotional state is shaken.
The Vietnam War itself caused many traumas, as it was a very violent war with many deaths and mutilations. In this way, soldiers who have returned alive have gone through many psychological dramas, alcohol vices, drugs, to the point of needing rehabilitation programs.
Answer: Popular sovereignty
A
To my knowledge, a senator needs to live in the US for 10 years
D. triangular trade happy to help ❤️