Robert Carneiro's theory of environmental circumscription holds that a. the environments in the areas where social complexity began are particularly suitable for agriculture, providing the surplus required b. when hostile environments halt village expansion, new farmland could only be taken from other villages by force c. when environments changed due to climatic changes, the only way for people to survive was to grant the chief greater power d. the need to defend lands with favorable environmental circumstances led to the emergence of an elite

d. the need to defend lands with favorable environmental circumstances led to the emergence of an elite.

Explanation:

Robert L Carneiro believes that environmental circumscription of an area is one of the most influencing factor that leads to rise of chiefdoms and societies in a region. An area with great potential to cultivate and flourish are sharply circumscribed and, thus, become more politically unified.

Therefore, the need to defend these lands with favorable environmental circumstances becomes necessary and as a result leads to the emergence of elites and powerful politically unified entities.

Carneiro believes that emergence of great civilizations in Maya Lowlands and West Africa were both results of environmental circumscription. He adds that absence of environmental circumscription may impede the process of state formation.