The idea of a fish being able to generate electricity strong enough to light lamp bulbs—or even to run a small electric motor—is

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问题     The idea of a fish being able to generate electricity strong enough to light lamp bulbs—or even to run a small electric motor—is almost unbelievable, but several kinds of fish are able to do this. Even more strangely, this curious power has been acquired in different ways by fish belonging to very different families.
    Perhaps the best known are the electric rays (鳐鱼),or torpedoes (水雷鱼),of which several kinds live in warm seas. They possess on each side of the head, behind the eyes, a large organ consisting of a number of cells which contain a series of flat electric plates. One side, the negative side, of each plate, is supplied with very fine nerves, connected with a main nerve coming from a special part of the brain. Current passes from the upper, positive side of the organ downwards to the negative, lower side. Generally it is necessary to touch the fish in two places, completing the circuit, in order to receive a shock.
    Another famous example is the electric eel (鳗鱼).This fish gives an even more powerful shock. The system is different from that of the torpedo in that the electric plates run along the length of its body and are supplied with nerves from the spinal cord (脊髓). Consequently, the current passes along the fish from head to tail. The electric organs of these fish are really altered muscles and like all muscles, they tend to tire easily, so they are not able to produce electricity for very long.
    The power of producing electricity may serve these fish both for defense and attack. If a large enemy attacks, the shock will drive it away; but it appears that the electric eel uses its current most often against smaller fish.
The most powerful electric fish produces enough electricity to______.

选项 A、light a large electric motor
B、kill a marine animal
C、drive a small electric motor
D、kill a large fish

答案C

解析 本题是一道具体细节题。问鱼放出的最强的电量可以做什么。根据文章第一段内容,谈到一条鱼能放电,而且电的强度足以点亮灯泡,甚至驱动小电机,几乎令人难以置信。但是,有几种鱼确能如此。更加奇怪的是,不同鱼类以不同的方式获得这种奇特的力量。由此我们可以推断本题的正确答案应是C“可以驱动小发动机”。
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