What characteristic is most closely associated with a caste system?

The characteristic most closely associated with a caste system is social hierarchy, where people are divided into different groups based on their birth and social status. In a caste system, individuals are often born into a specific caste, and their opportunities, jobs, and social interactions are largely determined by this caste. For example, in some cultures, a person born into a low caste might not be allowed to interact with or marry someone from a higher caste, limiting their social mobility. This system creates a rigid structure that can be difficult to change, as people usually stay in the same caste throughout their lives. Overall, the caste system emphasizes inequality and restricts individuals based on their social class from the moment they are born.