题目

阅读下面短文，从每题所给的A、B、C、D四个选项中选出可以填入空白处的最佳选项。Survivalin the AndesOn October 13, 1972, a smallplane flying to Chileaccidentally crashed into a mountain in the Andes.How some of the passengers 1 to live is one of thegreatest survival stories ever told. The survivors2 inside the remains (残骸)of the plane, using seat covers for blankets, and waited for a 3that never came. Days turned intoweeks. It was urgent to find a way to 4. Three of the passengers— Canessa, Parrado, andVizintin—volunteered to journey through the mountain（2007?荆门）区分日常的下列各组物质，鉴别方法正确的是（　　） 待鉴别的物质 鉴别方法 A 硬水、软水 看外观、观察是否澄清 B N2、O2、CO2、空气 用燃着的木条检验、观察木条燃烧的情况  C 羊毛纤维和化学纤维 灼烧闻气味，观察燃烧情况和灰烬 D 氮肥、磷肥、钾肥 加热石灰研磨，观察有无刺激性气味的气体放出A．AB．BC．CD．D