“少壮不努力，老大徒伤悲”这首诗在慨叹时光易逝，一去不返的同时，教育我们要养成（    )

材料一：第一条 凡未经议会同意，以国王权威停止法律或停止法律实施之僭越权力，为非法权力。

第二条：近来以国王权威擅自废除法律或法律实施之僭越权力，为非法权力。

材料二：我们认为下面这些真理是不言而喻的：人人生而平等，造物者赋予他们若干不可剥夺的权利，其中包括生命权、自由权和追求幸福的权利。

我们以这些殖民地的善良人民的名义和权力，谨庄严宣告：这些联合殖民地从此成为，而且名正言顺地应当成为自由独立的合众国，……

材料三：第一条 在权利方面，人们生来是而且始终是自由平等。

第六条 法律是公共意志的表现，在法律面前，所有的公民都是平等的。

第十七条 私人财产神圣不可侵犯。

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     Plants are very important. This is because plants can make food from air, water and sunlight. Animals and people can not make food from air, water and sunlight. Animals can get their food by eating plants and animals. People get their food by eating plants and animals, too. So animals and people need plants in order to live. This is why there are so many plants around us. There are two kinds of plants: flowering plants and non-flowering plants. You can know some trees from their flowers and fruits. Non-flowering plants do not grow flowers. You can not see many non-flowering plants around you. If you look carefully at the plants around us, you will find that there are many kinds of plants. Some plants are large and some are small. Most of them are green. Thanks to the plants around us we can live on the earth.

科学家通过实验分别研究了pH对酶A和酶B所催化的反应速率的影响，获得下图所示结果。下列有关叙述正确的是（  ）