Quick Answer
Strong AAMC PREview-style ethical reasoning usually does four things: gathers relevant facts, recognizes who could be affected, avoids hiding or minimizing misconduct, and uses the right level of support or escalation for the seriousness of the issue.
Weak responses tend to do the opposite. They ignore the affected person, protect a friend over a duty, jump to punishment before understanding the situation, share private information unnecessarily, or treat a serious problem as a casual interpersonal conflict.
Because AAMC PREview uses four response ratings, your job is not simply to choose the one “right” action. You need to judge whether each possible response is Very Ineffective, Ineffective, Effective, or Very Effective based on how well it addresses the ethical problem.