In a Replication of Zimbardo's Prison Experiment, Reported on the BBC

In a replication of Zimbardo's prison experiment, reported on the BBC:

A) for a time, prisoners coalesced into a cohesive group
B) the guards did not identify with the role and were reluctant to assert their authority
C) while guards and prisoners agreed to form an egalitarian commune, they could not agree on the rules
D) the prisoners ultimately failed to form a common social identity
E) all of the above