下列对有关主题知识的归纳错误的是（ ）
A．认识元素
空气中含量最多的元素-氮
地壳中含量最多的金属元素-铝
B．元素与人体健康
人体缺铁--最引起贫血
人体缺碘--易造成甲状腺肿大
C．生活常识
菜刀防生锈--用湿布包裹
煤炉取暖防中毒--室内放一盆水
D．环保与物质的利用
减少白色污染--使用可降解塑料
减少汽车尾气污染--使用乙醇汽油
A、空气中氮气体积分数为78%，所以氮气含量最多，地壳中最多的前五种元素是：氧、硅、铝、铁、钙，所以地壳中含量最多的金属元素是铝，故A说法正确；
B、人体缺铁会引起缺铁性贫血，人体缺碘--易造成甲状腺肿大，故B说法正确；
C、菜刀防生锈应保持表面洁净干燥，煤炉取暖中毒是一氧化碳中毒，由于一氧化碳难溶于水，所以室内放盆水不能防中毒，故C说法错误；
D、白色污染就是指一些塑料垃圾，所以使用可降解塑料可以减少白色污染，乙醇汽油中的乙醇燃烧后没有有害气体，所以使用乙醇汽油可减少汽车尾气污染，故D说法正确．
故选C．
阅读下面短文, 掌握其大意, 然后从1—10各题所给的A、B、C和D项中, 选出最佳选项, 并在答题卡上将该项涂黑。 Philo Farnsworth, the inventor of one of the country’s greatest machines was actually born in a log cabin, 1 to high school on horse back and without 2 of university degree（indeed, at age 14）, thought of the idea of electronic television. In 1906 Farnsworth was born in a community near Beaver City, Utah, 3 by his grandfather. 4 he was 12, his family moved to a ranch （大牧场）in Rigby, Idaho, which was four miles from, the nearest high school, 5 necessitating（使成为必要）his daily horseback rides. Because he was interested in the electron and electricity, he persuaded his chemistry teacher, Justin Tolman, to give him 6 instruction and to allow him to listen to a senior course. The death of his father forced him to leave at the end of his second year, but, as it 7 , at no great intellectual cost. There were, at the time, no more than a handful of men 8 the planet who could have understood Farnsworth’s idea for building an electronic television system, and it’s 9 that any of them were at this local community. One such man was Vladimir Zworykin who had moved to the US from Russia with a Ph. D in electrical engineering. He went to work for Westinghouse with a dream of building an all-electronic television system. But he wasn’t 10 to do so.
|