Some desert animals can survive the summer heat and dryness because they are very unusual. The camel, for example, can experienc

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问题    Some desert animals can survive the summer heat and dryness because they are very unusual. The camel, for example, can experience and bear an increase in the temperature of its body and its blood of 9°C without anything bad happening to it. In addition, it can drink a lot of water at one time; then store enough water in parts of its body to supply its needs for two weeks or more. The kangaroo rat, on the other hand, gets all the water it needs from water that it produces when it breathes. However, most animals need to maintain a fairly constant body temperature, and will die if it rises more than 5°C. Therefore, they need to find some way to stay away from the heat of the summer sun. Nor can many animals either store or produce water in their bodies, as the camel and kangaroo rat can. So they must find ways to keep their bodies from losing water because of the heat. Because very few desert animals can survive the high temperature of a typical summer’s day, most of them are active only in the night. Only after the sun has set does the desert come fully to life. The night is relatively cool. and the darkness provides protection, not only from the sun, but also from other animals and from the birds. So the coming of darkness is the signal for the large majority of animals and insects to start again their search for water and food. When morning comes, most of them seek shelter again: many go underground; nearly all find some dark and cool places where they, can keep away from the sun’s heat.
   For many kinds of insects, living in the desert is easier than for animals. Like many desert plant’s, they have a waterproof skin which prevents water loss because of the high temperature. In addition, some spend all or most of their life below ground. Here, for most of the year at least, it is moist, and it is generally cooler than on the surface. In the case of ants, only adults leave the underground nests, and they do so only to gather food or to defend the nest against attack.
It is easy for many kinds of insects to live in the desert because ______.

选项 A、They only need a little food to survive
B、they are not afraid of the heat
C、They are too small to be attacked by other animals
D、they have a skin which is against water

答案D

解析 由题干关键词many kinds of insects定位到最后一段第一、二句Like many desert plants, they have a waterproof skin which prevents water loss because of the high temperature.许多昆虫在沙漠中容易生存下来的原因是它们有一层能防水的皮肤,可以阻止因高温而蒸发体内水分。因此选[D]。[A]、[B]、[C]与文意不符,故排除。
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