请根据所学知识，简述下列现象的原因．

（1）明明生病了，几天吃不下食物，身体明显消瘦了．这是因为贮存在体内的____ 等营养物质消耗多而补充少的原因．

（2）医生检查后，建议明明点滴葡萄糖液来恢复体力．这是因为葡萄糖能为身体提供____ ，葡萄糖、淀粉、蔗糖都属于____ 

（3）明明康复以后，妈妈每天都让他多吃奶、蛋、鱼、肉，是因为这些食物中含有丰富的____ ．人的生长发育以及受损细胞的修复和更新，都离不开它．

（4）小明有一段时间，每到傍晚的时候就看不清东西，妈妈让他坚持每天吃点熟胡萝卜，这种现象就消失了．原因是于____ 

（5）广告中说“补钙关键在吸收”，除了补钙外，还应补充____ ．

阅读下面短文，从A、B、C、D四个选项中选出最佳选项。

    David is a good student at school, but he is not clean. His face and hands are often dirty. He washes them with water only. He doesn't like to use soap(肥皂). He has an aunt. His aunt comes to see him. She looks at David and says, " David, I know what you ate for breakfast this morning." "What?" David looks at his aunt and asks.

"Eggs," says his aunt. "Your face and mouth tell me that."

    "You are wrong, my dear aunt!" says David. "Not today or yesterday, but the day before yesterday."

158＋200－300的结果是____位数。

  2016年3月，我国通过了《长江经济带发展纲要》，如图为长江水系和长江经济带范围图，读图，完成以下问题。