14．American black bears appear in a variety of colors despite their name．In the eastern part of their range（地理分布區(qū)），most of these bears have shiny black fur，but in the west they grow brown，red or even yellow coats．To the north，the black bear is actually gray or white．Even in the same litter（窩），both brown and black furred bears may be born．
Black bears are the smallest of all American bears，ranging in length from 5to 6feet，weighing from 300to 500pounds．Their eyes and ears are small and their eyesight and hearing are not as good as their sense of smell．Like all bears，the black bear is shy，clumsy（笨拙的） and rarely dangerous．However，if cornered，the black bear can become a fearful enemy．
Black bears feed on leaves，roots，fruit，insects，fish and even larger animals．One of the most interesting characteristics of bears，including the black bear，is their winter sleep．Unlike many other animals，bears do not actually hibernate（冬眠）．Although the bear does not eat during the winter months，its temperature remains almost normal，and it breathes regularly four or five times per minute．
Most black bears live alone，except during the mating season （交配季節(jié)）．A litter of one to four cubs is born in January or February and they remain with their mother until they are fully grown or about one and a half years old．Black bears can live as long as thirty years in the wild，and even longer in game preserves set aside for them．
48．What do we know about the fur color of American black bears？B．
A．Most of them have black fur．
B．Their fur color depends on their living range．
C．They change their fur color throughout their life．
D．They are always of the same fur color as their brothers．
49．American black bears have a good sense ofA．
A．smell
B．hearing
C．eyesight
D．taste
50．Which of the following is TRUE about American black bears？A．
A．Their way of"hibernating"is unique．
B．They are able to live at most thirty years．
C．They are regarded as the smallest bear in the world．
D．The babies can soon live by themselves after birth．
