Final answer:
The subject of this question is Social Studies and the correct answer is 'Elites'.
Step-by-step explanation:
The subject of this question falls under Social Studies, specifically the study of political organization, power, and societal development.
Based on the provided information, the correct answer to the question is:
a) Elites
In this context, the theory suggests that powerful elites developed to protect the privileges of favored groups. The increasing social stratification and population growth in societies created the need for elites to secure their positions of power and resources. The elites would then use their authority to maintain control and influence over society.