水烧开时会看到壶嘴冒出白气，这是____现象，雪在阳光下化成了水，这是____现象，放在衣柜中的卫生丸变小，这是____现象．

材料  在1377年到1904年间获取进士的人中有42%来自下层社会。这种流动作为一种吸纳机制，增强了社会结构的弹性，并有利于对社会的驾取与整合。有学者把科举制度看作是古代联系社会动力和政治动力的纽带，是维护儒家学说正统地位的有效手段。

    科举制度的废除导致四民社会的解体与封建等级制的消亡，提高了农工商的地位。人们纷纷从“读书做官”的思想中解放出来，开始走向广阔的社会。1910年江苏省旧式士人从事实业者占比30.4%，新学堂毕业生与归国留学生从事实业者更是占比37%。一些士大夫开始办厂经商，如状元出身的孙家鑑、张春等在各地F击续投资办厂。科举制废除后各级各类学堂的大期実兴办，特别是女子教育的出现，扩大了教育对象。此外，新式课堂教学中逐步采用白话文取代文言文，而在教学内容上，传统的儒家经典只占27.1%，而数理化等新知识却占72.9%。这大大便利了近代新式教育的普及。

——杨齐福《科举制度的废除与近代社会的转型》

阅读下列短文，从每题所给的四个选项（A、B、C和D）中，选出最佳选项。

    Many facts suggest that children are overweight (超重的) and the situation is getting worse, according to the doctors. I feel there are a number of reasons for this.

    Some people blame the fact that we are surrounded by shops selling unhealthy, fatty foods, such as fried chicken and ice cream, at low prices. This has turned out a whole generation of grown-ups who seldom cook a meal for themselves. If there were fewer of these restaurants, then probably children would buy less take-away food.

    There is another argument that blames parents for allowing their children to become overweight. I agree with this, because good eating habits begin early in life, long before children start to visit fast food shops. If children are given fried chicken and chocolate rather than healthy food, or are always allowed to choose what they eat, they will go for sweet and salty foods every time, and this will carry on throughout their lives.

    There is a third reason for this situation. Children these days take very little exercise. They do not walk to school. When they get home, they sit in front of the television or their computers and play computer games. Not only is this an unhealthy pastime (消遣), it also gives them time to eat more unhealthy food. What they need is to go outside and play active games or sports.

    The above are the main reasons for this problem, and therefore we have to encourage young people to be more active, as well as steering them away from fast food shops and bad eating habits.