Final answer:
The correct order of socio-political structures from least to most complex is Band, tribe, chiefdom, and state. This sequence represents a scale of increasing complexity, centralization of power, and population size.
Step-by-step explanation:
In order of least to most complex, as well as fewest to most members, the four types of socio-political structures frequently discussed in anthropology are: Band, tribe, chiefdom, and state. This categorization reflects an increasing complexity and centralization of political power and authority, as well as a growth in population size and stratification. Bands represent the simplest form of human organization with no political structure, where decisions are made by consensus. Moving up in complexity, tribes have informal leadership often based on extended family structures or councils.
Chiefdoms are more centralized, with power being concentrated in a hereditary leader such as a chief. At the top of the complexity scale are states, which are large, centrally coordinated political systems with formal institutions and often a bureaucratic governance structure. In a historical context, the evolution of socio-political structures has interested anthropologists as societies developed from one form to another. These forms vary widely across different cultures and are influenced by factors such as subsistence strategies, population dynamics, and external pressures like trade and conflict.