Answer:
social stratification systems
Explanation:
Social stratification systems are defined as a phenomenon that tends to vary in the degree or extent of "vertical social mobility". Social stratification system mainly includes estate systems, slavery, class systems, and caste systems. In many western countries, the classless notion has not been included yet have less economic inequality rather than class society, for example, the United States.
In the question above, the given statement's ranking is an example of social stratification systems.
