阅读下面短文，掌握其大意，然后从36—55各题所给的四个选项（A、B、C和D）中，选出最佳选项，并在答题卡上将该项涂黑。

    Every day, I drive home along Colorado Blvd, a wide street with four lanes on each side of the median (中央分隔带护栏). I always notice a homeless man standing on the corner of Colorado Blvd, 1 for spare change with a sign in his hand.
Last Monday, when I was 2 him, he suddenly threw down his sign and rushed into the middle of the street. At this time I 3 a car moving across the 3 lanes of traffic and heading for the  median. The 4 man ran to the side of the car and attempted to push the car back in the right 5. He also knocked on the window of the vehicle, but all  6 Immediately, he ran across the small median into four lanes of oncoming traffic, 7 madly for the cars to stop. Thankfully, all speeding cars 8 to stop just in time to 9 hitting him. The car which was out of 10 came Moving across the median and the four lanes of traffic, where just seconds ago cars had been traveling with 11 speeds.
    The homeless man jumped back in front of the 12 to attempt slowing it down again. By this time, we were able to 13 and help the man stop the car 14 it ran into a supermarket on the other side of the road. As it 15 out, the woman driver had a heart attack while driving and became 16 in the front seat.
    The homeless man is indeed a hero. He spends every day getting 17 by people who are trying not to make 18 contact with him so that they don't feel bad not giving him money. Yet he didn't  even hesitate to risk his life to save this lady and other drivers who would have 19 into her. He didn't think of his safety, nor did he expect anything in return. Heroes do exist in the most 20 places.