阅读下列短文，从每题所给的四个选项（A、B、C、D）中，选出最佳选项，并在答题纸上将该选项标号涂黑。
A
In the lumberyard by the lake, where trees were turned into boards for construction work, there was an old brick building two floors high, and all around the outside walls were great piles of soft sawdust (锯木屑). That afternoon, bored with having nothing else to do, all the fellows followed Michael up the ladder to the roof of the old building and they sat there with their legs hanging over the edge. Suddenly Michael said, “I dare you to jump down,” and without thinking about it, he pushed himself off the roof and fell on the sawdust, where he lay rolling around and laughing. “I dare you all!” he shouted. “You’re all cowards (胆小鬼),” he said, encouraging them to follow him. Still laughing, he watched them looking down from the roof, white-faced and hesitant, and then one by one they jumped and got up grinning (咧嘴笑) with relief.
