Can animals be made to work for us?Some scientists think that on

Can animals be made to work for us?Some scientists think that one day animals may be trained to do a number of simple jobs that are now done by human beings. They point out that at a circus,for example,we may see elephants,monkeys,dogs and other animals doing quite skillful things．Perhaps you have seen them on the television or in a film．If you watch closely,you may notice that the trainer always gives the animal a piece of candy or a piece of fruit as a reward．The scientists say that many different animals may be trained to do a number of simple jobs if they know they will get a reward for doing them. Of course,as we know,dogs can be used to guard a house,and soldiers in both old and modem times have used geese to give warning by making a lot of noise when a stranger or an enemy comes near．But it may be possible to train animals to work in factories．In Russia,for example,pigeons which are birds with good eyesight,are being used to watch out for faults in small steel balls that are being made in one factory．When the pigeon sees a ball which looks different from others,it touches a steel plate with its beak．This turns on a light to warn people in the factory．At the same time a few seeds are given as a reward．It takes three to five weeks to train a pigeon to do this and one pigeon can inspect 3 000 to 4 000 balls an hour. Apes have been used in America in helping to make cars,and scientists believe that these large monkeys may be one day gather crops and even drive trains. What made scientists think animal can be made to work for us one day?
A、Animals are very skillful at a circu
B、They are big and stron
C、Some animals are as clever as human being
D、Animals can be trained because they like to get something as a rewar
【正确答案】：A
【题目解析】：根据文章内容，科学家认为动物可以被训练来为我们工作，这一观点主要基于他们观察到的动物在特定环境下所展现出的技能和学习能力。具体来说： A选项“Animals are very skillful at a circus”（动物在马戏团中非常熟练）是文章中明确提到的。科学家提到在马戏团中，我们可以看到大象、猴子、狗和其他动物做出相当熟练的事情，这是他们技能的一个直接证据。 B选项“They are big and strong”（它们大且强壮）虽然可能是某些动物的特点，但文章中并没有明确提及这是科学家认为动物可以被训练工作的原因。 C选项“Some animals are as clever as human being”（一些动物和人类一样聪明）虽然可能正确，但文章中并没有直接指出这是科学家认为动物可以被训练工作的原因。 D选项“Animals can be trained because they like to get something as a reward”（动物可以被训练是因为它们喜欢得到奖励）虽然提到了奖励在训练中的作用，但文章中的重点是动物展现出的技能，而不仅仅是它们对奖励的喜好。 因此，根据文章内容，是动物在马戏团等环境中展现出的熟练技能使得科学家认为动物有潜力被训练来为我们工作。所以正确答案是A。