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To many environmentalists, the extinction of plants—accompanied by the increasing genetic uniformity of species of food crops—is the single most serious environmental problem. Something must be done to prevent the loss of wild food plants or no-longer-cultivated food plants. Otherwise, the lack of genetic diversity could allow a significant portion of a major crop to be destroyed overnight. In 1970, for example, southern leaf blight destroyed approximately 20 percent of the United States corn crop, leaving very few varieties of corn unaffected in the areas over which the disease had spread. Which of the following can be inferred from the passage above

A. Susceptibility to certain plant diseases is genetically determined.
B. Eighty percent of the corn grown in the United States is resistant to southern leaf blight.
C. The extinction of wild food plants can in almost every case be traced to destructive plant diseases.
D. Plant breeders focus on developing plants that are resistant to plant disease.
E. (E) Corn is the only food crop threatened by southern leaf blight.

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In 1987 sinusitis was the most common chronic medical condition in the United States, followed by arthritis and high blood pressure, in that order. The incidence rates for both arthritis and high blood pressure increase with age, but the incidence rate for sinusitis is the same for people of all ages. The average age of the United States population will increase between 1987 and 2000. Which of the following conclusions can be most properly drawn about chronic medical conditions in the United States from the information given above

A. Sinusitis will be more common than either arthritis or high blood pressure in 2000.
B. Arthritis will be the most common chronic medical condition in 2000.
C. The average age of people suffering from sinusitis will increase between 1987 and 2000.
D. Fewer people will suffer from sinusitis in 2000 than suffered from it in 1987.
E. (E) A majority of the population will suffer from at least one of the medical conditions mentioned above by the year 20O0.

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To be mentally healthy, people must have self-respect. People can maintain self-respect only by continually earning the respect of others they esteem. They can earn this respect only by treating these others morally. Which of the following conclusions can be properly drawn from the statements above

A. People who are mentally healthy will be treated morally by others.
B. People who are mentally healthy will have treated morally those they esteem.
C. People who are mentally healthy must have self-respect in order to be treated morally by others.
D. People can expect to be treated morally by others only if they esteem these others.
E. (E) People who have self-respect seldom treat morally those they esteem.

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False rumors of fiscal improprieties damage the reputation of a bank. If management does not attempt to refute these rumors, they will circulate and eventually destroy customer confidence. But if management makes an effort to refute them, the refutation will raise more suspicions than it allays. If all of the statements above are true, which of the following must on the basis of them be true

A. The reputation of a bank cannot be influenced by heavy advertising campaigns.
B. True rumors of fiscal improprieties do not do as much damage to customer confidence in a bank as false rumors do.
C. The best strategy for bank managers to adopt in the face of false rumors of fiscal improprieties is to address them directly.
D. Management cannot prevent already existing false rumors of fiscal improprieties from threatening a bank’s reputation.
E. (E) A bank’s reputation for fiscal responsibility can be enhanced by favorable word of mouth.

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Politician: Unless our nation redistributes wealth, we will be unable to alleviate economic injustice and our current system will lead inevitably to intolerable economic inequities. If the inequities become intolerable, those who suffer from the injustice will retort to violence to coerce social reform. It is our nation’s responsibility to do whatever is necessary to alleviate conditions that would otherwise give rise to violent attempts at social reform. The statements above logically commit the politician to which one of the following conclusions

A. The need for political reform never justifies a resort to violent remedies.
B. It is our nation’s responsibility to redistribute wealth.
C. Politicians must base decisions on political expediency rather than on abstract moral principles.
D. Economic injustice need not be remedied unless it leads to intolerable social conditions.
E. (E) All that is required to create conditions of economic justice is the redistribution of wealth.

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