21. Naturalist： For decades we have known that the tuatara, a New Zealand reptile, has been approaching extinction on the South Island. But since South Island tuatara were thought to be of the same species as North Island tuatara there was no need to protect them. But new research indicates that the South Island tuatara are a distinct species, found only in that location. Because it is now known that if the South Island tuatara are lost an entire species will thereby be lost, human beings are now obliged to prevent their extinction, even if it means killing many of their unendangered natural predators.

Which one of the following principles most helps to justify the naturalists' argumentation？

（A） In order to maximize the number of living things on Earth. Steps should be taken to preserve all local populations of animals.

（B） When an animal is in danger of dying, there is an obligation to help save its life, if doing so would not interfere with the health or well-being of other animals or people.

（C） The threat of local extinction imposes no obligation to try to prevent that extinction, whereas the threat of global extinction does impose such an obligation.

（D） Human activities that either intentionally or unintentionally threaten the survival of an animal species ought to be curtailed.

（E） Species that are found in only one circumscribed geographical region ought to be given more care and attention than are other species because they are more vulnerable to extinction.

22. Nursing schools cannot attract a greater number of able applicants than they currently do unless the problems of low wages and high-tress working conditions in the nursing profession are solved. If the pool of able applicants to nursing school does not increase beyond the current level, either the profession will have to lower its entrance standards, or there will soon be an acute shortage of nurses. It is not certain, however, that lowering entrance standards will avert a shortage. It is clear that with either a shortage of nurses or lowered entrance standards of the profession, the current high quality of health care cannot be maintained.

Which one of the following can be property inferred from the passage？

（A） If the nursing profession solves the problems of low wages and high-stress working conditions, it will attract able applicants in greater numbers than it currently does.

（B） The nursing profession will have to lower its entrance standards if the pool of able applicants to nursing school does not increase beyond the current level.

（C） If the nursing profession solves the problems of low wages and high-stress working conditions, high quality health care will be maintained.

（D） If the nursing profession fails to solve the problems of low wages and high-stress working conditions, there will soon be an acute shortage of nurses.

（E） The current high quality of health care will not be maintained if the problems of low wages and high-stress working conditions in the nursing profession are no solved.

Questions 23-24

There are about 75brands of microwave popcorn on the market； altogether, they account for a little over half of the money from sales of microwave food products. It takes three minutes to pop corn in the microwave, compared to seven minutes to pop corn conventionally. Yet by weight, microwave popcorn typically costs over five times as much as conventional popcorn. Judging by the popularity of microwave popcorn, many people are willing to pay a high price for just a little additional convenience.

23. If the statements in the passage are true. Which one of the following must also be true？

（A） No single brand of microwave popcorn accounts for a large share of microwave food product sales.

（B） There are more brands of microwave popcorn on the market than there are of any other microwave food product.

（C） By volume, more microwave popcorn is sold than is conventional popcorn.

（D） More money is spent on microwave food products that take three minutes or less to cook than on microwave food products that take longer to cook.

（E） Of the total number of microwave food products on the market, most are microwave popcorn products.

24. Which one of the following statements, if true, would call into question the conclusion in the passage？

（A） More than 50percent of popcorn purchasers buy conventional popcorn rather than microwave popcorn.

（B） Most people who prefer microwave popcorn do so because it is less fattening than popcorn that is popped conventionally in oil.

（C） The price of microwave popcorn reflects its packaging more than it reflects the quality of the popcorn contained in the package.

（D） The ratio of unpopped kernels to popped kernels is generally the same whether popcorn is popped in a microwave or conventionally in oil.

（E） Because microwave popcorn contains additives not contained in conventional popcorn, microwave popcorn weighs more than an equal volume of conventional popcorn.

25. Situation： In the island nation of Bezun ,the government taxes gasoline heavily in order to induce people not to drive . It uses the revenue from the gasoline tax to subsidize electricity in order to reduce prices charged for electricity.

Analysis： The greater the success achieved in meeting the first of these objectives, the less will be the success achieved in meeting the second .

The analysis provided for the situation above would be most appropriate in which one of the following situations？

（A） A library charges a late fee in order to induce borrowers to return books promptly. The library uses revenue from the late fee to send reminders to tardy borrowers on order to reduce the incidence of overdue books .

（B） A mail-order store imposes a stiff surcharge for overnight delivery in order to limit use of this option. The store uses revenue from the surcharge to pay the extra expenses it incurs for providing the overnight delivery service.

（C） The park management charges an admission fee so that a park's users will contribute to the park's upkeep. In order to keep admission fees low ,the management does mot finance any new projects from them.

（D） A restaurant adds a service charge in order to spare customers the trouble of individual tips. The service charge is then shared among the restaurant's workers in order to augment their low hourly wages.

（E） The highway administration charges a toll for crossing a bridge in order to get motorists to use other routes .It uses the revenue from that toll to generate a reserve fund in order to be able one day to build a new bridge.