题目

I think all of us should know it’s necessary to have breakfast. It’s one of the most important meals of the day. If you want to keep fit， you should have a good breakfast. Choosing the right food is also important. For it， you may have bread， eggs and milk.But in fact， many students go to school without breakfast. This does harm to their health. Maybe they say they have no time because it’s too late or their parents are too busy to prepare breakfast for them. What will happen to the students on an empty（空的）stomach（胃）? Because of no energy， they can’t keep active物质的性质决定物质的用途。下列因果关系不成立的是（ ）A.因为磷燃烧能产生白烟，所以可用于制作烟幕弹B.因为金属钨的熔点高，所以被用来制造灯泡中的灯丝C.因为氮气化学性质不活泼，所以可用于食品包装袋内防腐D.因为氧气能支持燃烧，所以可用作燃料