In the Niger River valley, the primary urban settlement that has been excavated suggests:
A. that cities may develop without the need for hierarchy, centralization, government structure, or written language
B. the development of cities is contingent upon the development of a centralized political authority
C. written language is fundamental for the organization of an urban center
D. cities cannot develop without the pre-existence of hierarchical social organization
Answer: A. that cities may develop without the need for hierarchy, centralization, government structure, or written language