The correct answer is agriculture. It was made possible for people to live on a single piece of land and not be nomadic anymore in search of food. Agriculture enabled them to settle around river valleys like Nile or Tigris and Euphrates. This is the era when civilizations started rising worldwide.
Answer:
The Korean War is often called the “Forgotten War” in the United States because the 1950-53 conflict was overshadowed between World War II and Vietnam.
Explanation:
Mao's Red Guards started harassing Chinese intellectuals who supported capitalism
Mao's Red Guards ensured that all schools in China taught from Mao's Little Red Book.
I'd say pollution or disease.