What was the cultural importance of the annual flooding of the Nile River?

Which ecosystem best fits the characteristics listed below? which ecosystem best fits the characteristics listed below? ii. seasonal migrations of millions of wildebeests, zebras, and elephants iii. large numbers of predators, such as lions iv. acacia trees and grasses a. the congo rainforest b. the african mangroves c. the serengeti grasslands d. the sahel