(C)
One thing the tour books don’t tell you about London is that 2000 of its residents are foxes. They ran away from the city about two centuries ago after developers and pollution moved in . But now that the environment is clear the foxes have come home. “The number and variety of wild animals in urban areas is increasing” says Comer Jones. A survey of the wildlife in New York’s Central Park last year counted 14 species of mammals. A similar survey conducted in the 1890s counted only five species. Several changes have brought wild animals to the cities. Foremost is that air and water quality in many cities has improved as a result of the 1970s pollution-control efforts. Meanwhile , rural areas have been built up, leaving many animals on the edges of suburbs. In addition, urban wildlife refuges have been created. The Greater London Council last year spent￡750,000 buying land and building 10 permanent wildlife refuges in the city. As a result many birds are now living in the city. For peregrine falcons cities are actually safer than rural cliff dwellings (栖息地). By 1970 the birds had died out east of the Mississippi because of the DDT, which had made their eggs too thin to support life . That year, scientist Tom Cade of Cornell University began raising the birds for release in cities which afforded plenty of food. Cities can attract wild animals without turning them harmful. The trick is to create habitats where they can be self-sufficient but still be seen and appreciated . Such habitats can even be functional. In San Francisco, the local government is testing different kinks of rainwater control basins to see not only which ones retain the cleanest water but which will attract the most birds.
72．The passage is mainly concerned with___________.
A．wildlife returning to large cities     B．foxes returning to London
C．wild animals living in zoos            D．a survey of wildlife in New York
73.It can be inferred from the passage that__________      
A．Londoners are putting more and more wild animals into their zoos
B．Londoners are happy to see wild animals return to their city
C．Londoners are trying to move wild animals back to the countryside
D．Londoners have welcomed the wild birds, but found foxes a problem
74．According to the passage, the number of species of wildlife in New York’s Central Park______
A．is slowly decreasing               B．competes favorably with other cities
C．is on the same level as before  D．has more than doubled in the last century
75．Which of the following is NOT a reason that wildlife returning to the cities?
A．Food is plentiful in the cities
B．Wildlife is appreciated in the cities
C．Wildlife refuges have been built in the cities
D．Air and water quality has improved in the cities