Recall that in the Stanford Prison Study conducted by Philip Zimbardo and his colleagues (1973), guards became increasingly aggressive and prisoners became increasingly submissive and withdrawn, all in under a week. Results of this (aborted) study suggest that

a. social roles can take on a power all their own.

b. norms in the real world are often adopted in artificial settings.

c. humans are inherently aggressive and will "act out" in the appropriate situation.

d. interdependence can be reduced in powerful situations.