Which of the following describes an understood rule for expected behavior in society?

The term that describes an understood rule for expected behavior in society is "norm." Norms are the unwritten rules that govern the behavior of individuals within a group or society. They dictate how people are expected to behave in various situations, influencing everything from social interactions to cultural practices. Norms help maintain order and create predictability in social environments, allowing individuals to understand what is acceptable and expected in given contexts.

For instance, in many cultures, it is a norm to greet someone when you meet them, which facilitates social interaction and cohesion. Norms can vary greatly between different societies and may also change over time as cultural values evolve. This understanding of norms highlights their importance in shaping human behavior and interactions within social groups.