Answer:
O A
Explanation:
because it was essential for american indian allies
In ancient times<em> China</em> was isolated because of the mountains and rivers, they had the Himalayas and the Gobi, as good barriers. They believed that were alone in the world. Living in isolation made difficult to govern there, because of the large areas they had. This made people lived in different parts of China, create their own culture and costumes too, dialects, and way of speaking.
The Sahel part of Africa includes (from west to east) parts of northern Senegal, southern Mauritania, central Mali, northern Burkina Faso, the extreme south of Algeria, Niger, the extreme north of Nigeria, central Chad, central and southern Sudan, the extreme north of South Sudan, Eritrea, Cameroon, Central African Republic and the extreme north of Ethiopia
Traditionally, most of the people in the Sahel have been semi-nomads, farming and raising livestock in a system of transhumance, which is probably the most sustainable way of utilizing the Sahel. The difference between the dry North with higher levels of soil nutrients and the wetter South with more vegetation, is utilized by having the herds graze on high quality feed in the North during the wet season, and trek several hundred kilometers to the South to graze on more abundant, but less nutritious feed during the dry period
