下列关于有机物的说法正确的是（ ）
A．凡是含碳元素的化合物都属于有机物
B．有机物只含有碳、氢两元素
C．有机物不但存在于动植物体内，而且可以通过人工的方法合成
D．烃是指燃烧后只生成CO2和H20的有机物
A、凡是含碳元素的化合物不一定是有机物，如碳酸钠、二氧化碳、一氧化碳等组成结构与无机物相似属于无机物，故A错误；
B、有机物含有碳、氢两元素的叫烃，含碳、氢、氧元素的叫烃的衍生物，还可以含氮元素、硫元素等，故B错误；
C、有机物存在于动植物体内如淀粉、蛋白质等，也可以人工合成，如塑料、合成纤维等；故C正确；
D、烃的含氧衍生物燃烧后也生成CO2和H20，故D错误；
故选C．
Sneakers are a kind of shoes worn by many people all over the world. , no one really knows where the word “sneaker” came from. Some say it came from the old English verb “sneak”, which means to move silently and quickly. The only thing we are is that when you put on a pair of sneakers, you feel light-hearted, light-footed and ready to play.  Sneakers of some kind are used by those who play tennis, basketball, and other sports. New design has been made for people who run slowly. In fact American children of ages would much rather play in sneakers than anything else. New York City once held a poetry competition for children. The subject was only “sneaker”. One prize winner called poem “The Sneaker and the World Peace”. “When everyone is wearing sneakers,” she said, “it will be impossible to .” American school children can be seen every day sneakers of all colors. They put them on in the morning and take them off at bedtime. Sneakers are washed. Some children think the older and dirtier they are, the loveable they are. When their sneakers wear out, children hate to throw them off. How do you explain the closeness between and sneakers? Perhaps another young winner in the New York Poetry Contest said it best. “A shoe is just a shoe,” he said. “But a sneaker is a friend.”
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