Depending on how you frame things I think 1 is your best bet because it is framed as the most "personal" challenge you have directly faced. The topic of #3 may go well with a question along the lines of advocacy/standing up for marginalized communities, which does come up decently often in secondaries. Topic #2 I think would fit best for a question along the lines of "going through an uncertain situation" and/or an ethically challenging/ambiguous situation.