In the Stanford Prison Study, Male College Students Agreed to Participate

In the Stanford prison study, male college students agreed to participate in a two-week experiment to discover what would happen when they took on the roles of prisoners and guards. The researchers found that:

A) since the study was conducted in an unused wing of a real prison, the realistic atmosphere enhanced the role behaviour of prisoners and guards.
B) within a short time the prisoners became distressed and panicky, developing emotional symptoms and physical ailments.
C) about 5% of the guards became tyrannical, giving the prisoners electric shocks when they were slow in obeying.
D) 90% of the guards tried to be "tough but fair" and demanded that the tyrannical guards lighten up on the prisoners because it was only an experiment.