Zimbardo's Standford Prison Experiment Was a True Experiment Because Subjects

Zimbardo's Standford prison experiment was a true experiment because subjects were randomly assigned to the role of prison or guard. The experimental design of this study enabled Zimbardo to determine with a high degree of certainty:

A) how the location of a prisoner's cell influences his patterns of interaction within the prison
B) how random people join together to resist authority through collective action
C) how prior experiences shape people's reactions to the guard role
D) whether gender affects prison guards' behaviors
E) whether it is personality or the prison environment that makes prison guards act in a sadistic manner