单项选择题 The main idea of the second paragraph is that ________. A．our health will be harmed if we eat everything B．all kinds of food should be eaten to keep good balance C．we should eat all kinds of food but not too little D．we should eat more of some kinds of food than others

未知题型 关于商品归类总规则下列说法正确的是（ ）。 A．类、章及分章的标题在仅供查找方便而设，它们不是商品归类的法律依据 B．具有法律效力的归类应按品目条文和有关类注或章注确定 C．在对商品进行归类的时候，如果按品目条文、及相关的章注、类注还无法确定归类的，才依次按规则二、三、四、五、六来归类 D．未装配或拆卸开进出口的具有完整品或制成品的本质特征的非完整品或未制成品，作为完整品或制成品归类

单项选择题 Proteins are found ________. A．only in meat B．in all kinds of food C．more in vegetables than in meat D．in some vegetables as well as in meat