题目

The word “conservation” has a thrifty meaning. To conserve is to save and protect, to leave what we ourselves enjoy in such a good condition that other s may also share the enjoyment. Our forefathers had no idea that human population would increase faster than the supplies of raw materials: most of them, even until very recently, had the foolish ideas that the treasures were “limitless” and could “last forever”. Most of the citizens of earlier generations knew little or nothing about the complicated and delicate system that runs all through nature, and which means that, as in a liv5．下列调査中，适合用全面调查方式的是（　　）A．了解某校七年级（1）班学生期中数学考试的成绩B．了解一批签字笔的使用寿命C．了解市场上酸奶的质量情况D．了解某条河流的水质情况