In the Stanford Prison Study, subjects were randomly assigned to be prisoners and guards in the experiment. The guards wore khaki prison uniforms, carried night sticks, and wore sunglasses while the prisoners wore prison garb with their prison numbers on the back. These costumes signified the each of the subjects was to play in the experiment.

social roles            

Explanation:

Social role: In psychology, the term "social role" is described as behaviors, expectations, and responsibilities that an individual ought to adapt in a few specific situations. However, the normal or expected behavior that is being reinforced by society as well as individual. Therefore, every individual tends to take or exhibit many distinct roles and keeps on changing or shifting those roles throughout his or her life.

In the question above, the given statement represents social roles.

answer; /// working class;