大学英语四级阅读理解练习 一

　　 Questions 16 to 20 are based on the following passage:
　　 The black robin （知更鸟）is one of the world's rarest birds. It is a small, wild bird, and it lives only on the island of Little Mangere, off the coast of New Zealand. In 1967 there were about 50 black robins there; in 1977 there were fewer than ten. These are the only black robins left in the world. The island has many other birds, of course, of different kinds, large and small; they seem to multiply very happily.
　　 Energetic（有力的，积极的）steps are being taken to preserve the black robin-to guard those remaining and to increase their number. Detailed studies are going on, and a public appeal for money has been made. The idea is to buy another island nearby as a special home, a "reserve", for threatened wild life, including black robins. The organisers say that Little Mangere should then be restocked with the robin's food--it eats only one kind of seed--and so renewed for it. Thousands of the required plants are at present being cultivated in New Zealand. The public appeal is aimed at the conscience of mankind, so that the wild black robin willl not die out and disappear from the earth in our time at least.
　　 In the earth's long, long past hundreds of kinds of creatures have evolved, risen to a degree of success--and died out. In the long, long future there will be many new and different forms of life. Those creatures that adapt themslves successfully to what the earth offers will survive for a long time. Those that fail to meet the challenges will disappear early. That is Nature's proven method of operation.
　　 The rule of selection--"the survival of the fittest" is the one by which man has himself arrived on the scene.
　　 Life seems to have grown too tough for black robins.
　　 16.The black robin is dying out mainly because________.
　　 A) people have been very careless about its survival
　　 B) its only food is becoming exhausted on Little Mangere
　　 C) the other birds on the island have destroyed it
　　 D) the appeal for money has come at the wrong time
　　 17.The success of other small birds on Little Mangere shows that________.
　　 A) the island cannot have very much food left
　　 B) something has to die out, they can't all be winners
　　 C) the big birds have all been attacking the black robin
　　 D) the robin has failed to meet the challenges of life
　　 18.As regards selection and survival, the decisive factor seems to be________.
　　 A) the ability to adapt to changed or changing conditions
　　 B) the number of wild life reserves that are available
　　 C) the concern and generosity（慷慨）of the public
　　 D) the size of the home, or the amount of space one has to live in
　　 19.The evidence seems to suggest that________.
　　 A) it is a disaster for everyone when one kind of bird dies out
　　 B) all creatures are concerned about the survival of others
　　 C) Nature expects and accepts the dying out of weaker breeds
　　 D) man is to blame when such a thing happens
　　 20.The writer's attitude towards the protection of the black robins is _________.
　　 A) active
　　 B) passive
　　 C) indifferent
　　 D) pessimistic