The correct answer to this open question is the following.
Although there are no options attached, we can say the following.
The implication did Philip Zimbardo's Stanford prison experiment (1973) had for understanding such atrocities as American soldiers' abuse of Iraqi prisoners at Abu Ghraib was the following.
Professor Philip Zimbardo found that prisons were terrible places and the balance of power there was unequal. Life in a prison tended to corrupt the conduct and behavior of people who had the power and controlled the place. The only thing that could limit this conduct was the presence of firm regulations and close monitoring of these regulations in place.
Professor Philip Zimbardo performed this experiment in the basement of the school of Psychology at Stanford University in Palo Alto, California. There he created the mock prison in 1973.