人们都知道，鸡、猫、狗等动物和人身上都是热乎乎的，蛇身上却是冷冰冰的。前者叫“恒温动物”，后者叫“变温动物”。恒温动物的身体像恒定的炉子，为了保持体温的恒定，就要消耗体内的能量物质来维持。______，拿重量相等的猪和大蟒蛇相比较，如果猪每消耗150份重量的能源物质，那么，蛇只要一份就够了。冬眠的蛇消耗更是微乎其微，经历长达五个月冬眠期的蛇，其体重只减轻2%左右。 填入横线上最恰当的是( )。
A．而变温动物的蛇类就省去了这笔能量开支
B．而蛇是变温动物
C．而蛇可以省去这笔能量开支
D．而变温动物可以省去这笔能量开支
参考答案：A
解析： 做这样的题，要注意上下文的连贯性，横线前面的句子的主语是“恒温动物的身体”，而且在这里有转折词“而”，所以横线上都填入“而变温动物的蛇类……”才能使上下文连贯。故选A。
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| Once, in a small village, lived a family with eight children. Two of the children loved 1 very much, but the family was so poor that it was impossible to send both of them to study at the art college at the same time. After many discussions, the two boys finally 2 a plan. They would toss (抛) a coin. The loser would go 3 into the mines (煤矿) and, with his earning (赚的的钱), 4 his brother studying at the college. Then, when the brother who won the toss finished his studies, after four years, he would support the other brother studying at the 5 . James won the toss and Jack went down into the mines. James worked with all his heart and his paintings were much 6 than those of most of his teachers, and by the time he graduated, he was beginning to make a lot of money for his paintings. 7 James returned, the family held a big dinner for his great success. Soon after the meal began, James 8 up from his seat to drink a toast (举杯祝酒) to his dear brother. He said, "Jack, now you can go to the art college and your 9 will come true. I will take care of you." But Jack said 10 , "Brother, the four years in the mines has done too much to my hands. It's too 11 . Now I can't even hold a glass." To show his great love and respect, James drew his brother's hands with 12 towards the sky. He called his drawing "The Praying Hands", which became very famous years later. | ||||
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