Question

which event marked the end of the vietnam war?
north vietnamese forces returned american pows.
us troops withdrew from vietnam.
south vietnam surrendered after saigon fell.
the united states reduced its involvement in vietnam.

Explanation:

The fall of Saigon led to South Vietnam's surrender, effectively ending the Vietnam War. Returning POWs, US troop withdrawal, and reduced US involvement were important events but not the end - markers.

Answer:

South Vietnam surrendered after Saigon fell.