May people like the gigantic whales. Human sympathy【C1】______ whales is onl

游客2023-09-09  25

问题      May people like the gigantic whales. Human sympathy【C1】______ whales is only natural of all the creatures in the sea.【C2】______ are closer relatives to us than these warm-blooded mammals. And how they got into the sea is one of the most fascinating stories of【C3】______ . Most authorities believe that 60 million years ago ancestors of modern whales were four-legged, wolf-size animals living on the sea shores,【C4】______ an abundance of fish and shrimp tempted them to try wading.【C5】______ 10 to 15 million years, their bodies grew, forelegs shrank into flippers used for balance and steering and hind legs disappeared. As a result of some amazing transformations, they are now helpless on land. If stranded on a beach, they can barely breathe.
     With abundant 【C6】 ______ of food, whales grew into the largest creatures that lived,【C7】______ larger than dinosaurs. A blue whale can grow to 100 feet. Its tongue is ten feet thick and heavier than an elephant. Some arteries are big enough for a child to swim【C8】______ . The half-ton heart has walls two feet thick and pumps eight tons of blood.【C9】______ its size comes awesome strength. A blue whale swimming 【C10】______ 15 knots generates 1 000 horsepower.【C11】______  their size, these giants move at a good speed. An 18-ton whale can even【C12】______ 12 m. p. h., over short distances. A whale can 【C13】______ to 9 000 pounds of food a day. The world’s biggest creature【C14】______ itself almost entirely on shrimp-like krill, smaller than a person’s thumb.
     Maternal instincts are also【C15】______ Because a calf is born underwater, the mother must get it to the surface before it【C16】______ . Often another whale will help. The mother pushes it gently【C17】______ the baby is confident with its swimming—usually after about 30 minutes. If the calf is【C18】______ , she may support it on her back until it gradually rots away. Like all mammals, whale babies【C19】______ mother’s milk. And the milk is more than 30-percent fat, over 10-percent protein, and the babies grow extremely fast. A blue whale calf lengthens【C20】______ two inches a day and gains an average seven pounds per hour.  [br] 【C3】

选项 A、revolution
B、resolution
C、solution
D、evolution

答案 D

解析 名词辨析题 。本句的意思为“鲸鱼如何进入海洋是进化史上最引人关注的故事之一”,而且下文介绍了鲸鱼的进化过程,所以本题应选择evolution“生化,演变”。
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