阅读下列短文，从每题所给的四个选项中（A、B、C、D）中，选出最佳选项。"

    You're rushing to work and a man ahead of you falls down on the sidewalk. Do you stop to help? In a study of by-standers, it was found that some people keep on walking.

    "There is a tendency to decide that no action is needed," says a psychologist, "In order to take action, you have to work against them." Here are some common thoughts that stop you from helping.

    ●Why should I be the one? I'm probably not the most able person in this crowd. You might think someone older or with more medical knowledge should offer assistance.

    ●What if he doesn't really need my help? The fear of embarrassment is powerful; no one wants to risk looking foolish in front of others.

    ●No one else looks concerned. We can follow the people around us, but most people tend to hold back their emotions in public.

    "If you spot trouble and find yourself explaining inaction, force yourself to stop and evaluate the situation instead of walking on," says the psychologist. "Then retry to involve other people; you don't have to take on the entire responsibility of being helpful. Sometimes it's just a matter of turning to the person next to you and saying, 'It looks like we should do something.' Or asking someone if an ambulance has been called and, if not, to call for one. Once you take action, most people will follow you."