阅读理解

　　Plants are very important living things．Life couldn’t go if there were no plants．This is because plants can make food from air, water and sunlight．Animals and man cannot make food from air, water and sunlight．Animals get their food by eating plants and other animals．So animals and man need plants in order to live．This is why we find that there are so many plants around us．

　　If you look carefully at the plants around you, you will find that there are two kinds of plants：flowering plants and non-flowering plants．

　　Flowering plants can make seeds(种子)．The seeds are protected by the fruits．Some fruits have one seed, some have two, three or four, and some have many seeds．But a few fruits have no seeds at all．An example of a fruit without seeds is the banana fruit．

　　Most non-flowering plants don’t grow from seeds．They grow from spores(孢子)．Spores are very, very small．Some spores are so small and light that they can float(漂浮)in the air．We may say that spores are quite the same as the seeds．When these spores fall on wet and shady(阴凉的)places, they usually grow into new plants．

根据短文内容，从题中所给的A、B、C、D四个选项中，选出正确答案。

阅读理解

　　All living things on the earth need other living things to live．Nothing lives alone．Most animals must live in a group, and even a plant grows close together with others of the same kind．Sometimes one living thing kills another, one eats and the other is eaten．Each kind of life eats another kind in order to live, and together they form a food chain(食物链)．Some food chains are simple, while others are not．But all food chains begin with the sun, and all food chains will be broken up if one of the living things disappears(消失)．

　　All life needs sunlight to live on．But only plants can use sunlight directly．Plants are “factories”．They make food from sunlight, water, air and things in the soil．

　　Plants feed all other living things．Animals can only use the sun’s energy after it has been changed into food by plants．Some animals feed directly on plants, others eat smaller animals．Meat-eating animals are only eating plants indirectly．

　　What about human beings? We are members of many food chains．We eat wheat, rice, vegetables, fruit and so on．We also eat meat and drink milk．But men often break up the food chains．They kill wild animals．They also make rivers, lakes and seas dirty．When these rivers, lades and seas are polluted, the fish in them can not be eaten．If men eat the fish, they will get strange diseases(疾病)．

　　Each form of life is linked to the others．Breaking the links will put all lives in danger．