World war three is the answer
Answer:
Farmers needed to dispose of farm-animal waste to keep water supplies clean. Fertilizer made the soil capable of growing plants brought from other continents. Adding fertilizer to the soil prevented farmers from having to use slash-and-burn techniques.
Explanation:
hope it helps
Answer: C. High crop yields on fertile floodplains permitted more people to pursue non-farming activities. d People stopped conducting warfare on neighboring groups.