The Stanford Prison Experiment by Philip Zimbardo Was a Simple

The Stanford Prison Experiment by Philip Zimbardo was a simple experiment where participants were recruited to spend two weeks in a simulated prison in the basement of Stanford University. They were randomly assigned to either play the role of prisoners or guards. Even though all participants knew the situation was artificial and that they were being monitored by the experimenters, the experiment was stopped within a few days because

A) experiments had planned for a short study.
B) abuse of the prisoners by the guards had deteriorated so much.
C) treatment of the prisoners by the guards was so nice that is was not realistic.
D) the prisoners attacked the guards.