Passage five  Animal life first appeared on the earthabout 400 million years ago. Through the passing millennia, thousands of animalspecies have come and gone. Until recently, this process was gradual, theresult of changes

Passage five  Animal life first appeared on the earthabout 400 million years ago. Through the passing millennia, thousands of animalspecies have come and gone. Until recently, this process was gradual, theresult of changes in climate, in habitat, or in the genes of the animalsthemselves. But the tremendous expansion of modern civilization now threatensto upset this natural balance, putting unprecedented pressure on the survival ofour wildlife.  Of all the continents, the most drasticreduction in wildlife has occurred in North America, where the transition froma rural to a highly industrialized society has been most rapid. Among thevictims are birds, mammals, and fish. We will never again see the passengerpigeon or the eastern elk. They have been wiped out. Of many other species,only a few representatives still survive in the wild. The U. S. Department ofthe Interior has put no fewer than 109 species on the endangered species list.This list includes everything from the timber wolf to the whooping crane. Eventhe bald eagle, our national symbol, is threatened.  Animals that kill other game for food arecalled predators. The predators include the wolf, mountain lion, fox, bobcat, andbear. Attack against these animals began with the arrival of the first Europeansettlers, who wished to protect their livestock. Eventually, a reward wasoffered to hunters for every predator that was killed. This reward is called abounty. Ironically, the Federal government was the chief founder ofpredator-control programs.  The settlers also brought with them theirOld World fears and superstitions concerning predators. Whether preying onlivestock or not, predators were shot on sight. This attitude continues to thisday for coyotes,eagles,foxes,mountain lions,and bobcats,and is largelyresponsible for placing the eastern timber wolf,grizzly bear, and bald eagle onthe endangered species list.  Yet every animal,including the predator,has its place in nature’s grand design. Predators help maintain the health oftheir prey species by eliminating the diseased,young,old,and injured. Predatorslike the mountain lion and the wolf help to keep the deer herds healthy. Theirkill also provides food for scavengers that feed on carrion. Occasional loss oflivestock must be weighed against the good these animals do in maintaining thebalance of nature. 
Bounty hunters are those who____.()

A.take care of the wild areas

B.kill predators for money

C.preserve wild animals

D.protect the habitat of the wildlife

正确答案是B