题目内容：
请根据短文内容，回答题。 Why India Needs Its Dying Vultures
The vultures ( 秃鹰 )in question may look ugly and threatening, but the sudden sharp decline in three species of India's vultures is producing alarm rather than celebration, and it presents the world with a new kind of environmental problem. The dramatic __________(51) in vulture numbers is causing widespread disruption to people living in the__________ (52) areas as the birds.
It is also causing serious public health problems __________ (53) the Indian sub-continent.
While their reputation and appearance may be unpleasant to many Indians, vultures have__________ (54) played a very important role in keeping towns and villages all over India__________.(55).
It is because they feed on dead cows. In India, cows are sacred animals and are __________ .(56) left in the open when they die in their thousands upon thousands every year.
The disappearance of the vultures has__________ (57) an explosion in the numbers of wild dogs feeding on the remains of these__________(58) animals. There are fears that rabies (狂犬症)may increase as a result. And this terrifying disease may ultimately ( 最终 ) affect humans in the region,__________(59) wild dogs are its main carriers. Rabies could also spread to other animal species, __________ (60) an even greater problem in the future.
The need for action is__________(61), so an emergency project has been launched to find a solution to this serious vulture problem. Scientists are trying to __________. (62) the disease causing the birds' deaths and, if possible, develop a cure.
Large-scale vulture__________(63) were first noticed at the end of the 1980s in India. A population survey at that time showed that the three species of vultures had declined__________(64)over 90 per cent. All three species are now listed as "critically endangered". As most vultures lay only single eggs and__________ (65) about five years to reach maturity, reversing their population decline will be a long and difficult exercise.
__________ A．increase
B．threat
C．Risk
D．decline
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