提高一个生态系统的自我调节能力，最有效的方法是（　　）

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2004年12月26日，苏门答腊岛附近发生了40年来最严重的海啸，夺去了近30万人的宝贵生命，海啸无情人有情，世界各国纷纷伸出援助之手，中国政府在捐助了大批物质的同时，还派出医疗救护人员，他们不畏艰险，克服困难，曾在废墟中救出一位被困30多小时的女婴，发现除明显消瘦外，其他一切生理指标基本正常．请分析该女婴重量减轻最明显的是（  ）

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    Uncle Wangworks in 1 bookstore in the middle of the city. The shop is not far from his home. It is about three kilometers (公里) away. So Uncle Wang seldom (很少) 2 to work by bus. He usually goes there 3 bike, sometimes on foot. It takes him ten minutes to get there by bike and forty minutes on foot. Today his bike is broken.  He wants to walk there. Now he is having breakfast. At ten to eight, he leaves home and walks to work.  It's twenty 4 earlier than usual.  His work starts at half past eight in the morning and 5 at a quarter (一刻钟) to five in the afternoon.