题目

阅读理解     As the world's largest terrestrial carnivore(陆地肉食动物), the polar bear is the king of the great white north. Adult males can measure more than 9 feet in length and weigh between 770 and 1430 pounds. The polar bear has a strong body while their heads are narrow with small, rounded ears.     Polar bears can be found in northern Canada, Greenland, Norway and Russia, and there have been reports that polar bear tracks have been found as far north as the North Pole. The 5, 000, 000-square-mile range of the polar bear circles the Arctic and contains pieces of open water where seals are easily caught.     Polar bears live on the annual Arctic sea ice that provides a platform from which they can hunt. They hunt seals on the sea ice by breaking into seal dens in the sea ice. The dens aren't visible from above, but seeing is less important than smelling to a polar bear—with their sharp sense of smell, polar bears can sense the breathing holes of seals in their dens beneath the snow and ice. As the southern edge of the Arctic ice cap melts in summer, polar bears are forced to stay on land and spend their summers fasting(禁食), living off body fat stored from hunting in spring and winter.     With about 22, 000 polar bears living in the wild, the species is not endangered at the moment, but its future is far from certain. Climate change is causing the disappearance of sea ice from which polar bears hunt seals. Sea ice in the Arctic is melting earlier and forming later each year. People have reached an agreement that controls the hunting of polar bears and directs each nation to protect their habitats, but it does not protect the bears against the biggest man-made threat to their survival: global warming. If current warming trends continue, scientists believe that polar bears may disappear within 100 years. （1） Polar bears search for seals mainly through their       . A . eyes B . ears C . noses D . necks （2） The underlined word "dens" in Paragraph 3 most probably means "      ". A . the skin of the wild animals B . the home of wild animals C . the breathing hole of seals D . water of the deep sea （3） Which of the following statements is true? A . A polar bear measures at least 9 feet long. B . Polar bears can be found in both the North Pole and the South pole. C . Polar bears stop hunting in summer because seals are hidden at that time. D . Polar bears may die out as a result of climate change. 答案： C B D

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