【单选题】

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An animal species becomes extinct when it fails to produce enough young in each generation to keep pace with the death-rate. We can (26) from fossil evidence in rocks that many living species have become extinct over the millions of years (27) life began. It is a natural (28) and extinction is the (29) of any animal that has specialized too far to change (30) its environment changes, or has to compete with a better- (31) and more powerful animal. (32) remarkable technical developments during the past few centuries, man has destroyed or (33) destroyed some species by killing them (34) such a rate that they couldn’t produce enough offspring, or by completely changing their natural environment at surprising speeD、
A、number of examples can be given of the way (35) which natural environments are being rapidly changed—Amazonia, for instance. There is every (36) that many species of animals will be made extinct because of these and similar (37) of natural vegetation. Large numbers of animals have been hunted and killed for fooD、The NorthAmerican buffalo is a (38) of the near-extinction of a species through hunting. Often the numbers are (39) great that the hunters may not realize the danger.But even when the danger is widely (40) , the financial rewards for the hunters may be so great that they choose to (41) the threat to the species.Attitudes like this have (42) to hunters killing animals for furs, for ivory or merely for ornaments.A、slight (43) on this is when tourists hunt animals for trophies. Such magnificent creatures (44) lions and tigers (45) out of existence in some parts of the worlD、
A．at
B．over
C．to
D．for