Being an only child has little to do with a child s social development. A recent study tha

were found more likely than other sedentary middle-aged men to have a high blood level of cholesterol, which is a factor increasing risk of heart disease. Cholesterol can reach the blood from food and drink but is not contained in coffee. Which of the following, if true, most seriously weakens a conclusion from the study that for sedentary middle-aged men coffee increases the risk of heart attack?

A．A sedentary style. of life increases levels of cholesterol in the blood.

B．Coffee contains caffeine, which acts as a stimulant that increases heart rate.

C．The men studied drank their coffee without milk or cream, which contain cholesterol.

D．In both groups, the men were likely to be overweight, and excess weight is a factor that increases risk of heart diseases.

E．The men who drank more than two cups of coffee a day also ate more foods high in cholesterol.

antly in a rural county this year, as compared to last year, health officials attribute this decrease entirely to improved sanitary conditions at water-treatment plants, which made for cleaner water this year and thus reduced the incidence of the disease. Which of the following, if true, would most seriously weaken the health officials explanation for the lower incidence of the disease?

A．Many new water-treatment plants have been built in the last five years in the rural county.

B．Bottled spring water has not been consumed in significantly different quantities by people diagnosed as having the intestinal disease, as compared to people who did not contract the disease.

C．Because of a new diagnostic technique, many people who until this year would have been diagnosed as having the intestinal disease are now correctly diagnosed as suffering from intestinal ulcers.

D．Because of medical advances this year, far fewer people who contract the intestinal disease will develop severe cases of the disease.

E．The water in the rural county was brought up to the sanitary standards of the water in neighboring counties ten years ago.

es account for forty percent of the cost of manufacturing gauges at both Shelby Industries and Jones Industries. Shelby Industries is seeking a competitive advantage over Jones Industries. Therefore, to promote this end, Shelby Industries should lower employee wages. Which of the following, if true, would most weaken the argument above?

A．Because they make a small number of precision instruments, gauge manufacturers cannot receive volume discounts on raw materials.

B．Lowering wages would reduce the quality of employee work, and this reduced quality would lead to lowered sales.

C．Jones Industries has taken away twenty percent of Shelby Industries business over the last year.

D．Shelby Industries pays its employees, on average, ten percent more than does Jones Industries.

E．Many people who work for manufacturing plants live in areas in which the manufacturing plant they work for is the only industry.

is company requires all employees to arrive at work at 8 a.m. The proposed policy would permit each employee to decide when to arrive—from as early as 6 a. m. to as late as 11 a. m. The adoption of this policy would be most likely to decrease employees productivity if the employees job functions required them to

A．work without interruption from other employees.

B．consult at least once a day with employees from other companies.

C．submit their work for a supervisor"s eventual approval.

D．interact frequently with each other throughout the entire workday.

E．undertake projects that take several days to complete.

eople a great deal more than nonaddicts do. The researcher concluded that people who frequently manipulate other people are likely to become addicts. Which of the following, if true, most seriously weakens the researchers conclusion?

A．After becoming addicted to drugs, drug addicts learn to manipulate other people as a way of obtaining drugs.

B．When they are imprisoned, drug addicts often use their ability to manipulate other people to obtain better living conditions.

C．Some nonaddicts manipulate other people more than some addicts do.

D．People who are likely to become addicts exhibit unusual behavior. patterns other than frequent manipulation of other people.

E．The addicts that the researcher studied were often unsuccessful in obtaining what they wanted when they manipulated other people.

ment program would award low-income families a refund on the income taxes they pay of as much as $ 1, 000 for each child under age four. This program would make it possible for all low-income families with children under age four to obtain more child care than they otherwise would have been able to afford. Which of the following, if true, most seriously calls into question the claim that the program would make it possible for all low-income families to obtain more child care?

A．The average family with children under age four spends more than $ 1,000 a year on child care.

B．Some low-income families in which one of the parents is usually available to care for children under age four may not want to spend their income tax refund on child care.

C．The reduction in government revenues stemming from the income tax refund will necessitate cuts in other government programs, such as grants for higher education.

D．Many low-income families with children under age four do not pay any income taxes because their total income is too low to be subject to such taxes.

E．Income taxes have increased substantially over the past twenty years, reducing the money that low-income families have available to spend on child care.

rtain fixed date, with the actions of each conditional on simultaneous action taken by the other countries. Each country was also to notify the six other countries when it had completed its action. The simultaneous-action provision of the treaty leaves open the possibility that

A．the compliance date was subject to postponement, according to the terms of the treaty.

B．one of the countries might not be required to make any changes or take any steps in order to comply with the treaty, whereas all the other countries are so required.

C．each country might have a well-founded excuse, based on the provision, for its own lack of compliance.

D．the treaty specified that the signal for one of the countries to initiate action was notification by the other countries that they had completed action.

E．there was ambiguity with respect to the date after which all actions contemplated in the treaty are to be complete.

rage age of CEOs in those same companies 20 years ago was approximately eight years younger. On the basis of those data, it can be concluded that CEOs in general tend to be older now. Which of the following casts the most doubt on the conclusion drawn above?

A．The dates when the CEOs assumed their current positions have not been specified.

B．No information is given concerning the average number of years that CEOs remain in office.

C．The information is based only on companies that have been operating for at least 20 years.

D．Only approximate information is given concerning the average age of the CEOs 20 years ago.

E．Information concerning the exact number of companies in the sample has not been given.

d their parents frequently being in pain were also those who experienced common pains, like headaches, most frequently as adults. This evidence argues that a person s childhood observations of adults in pain can make that person more susceptible to pain as an adult. Which of the following, if true, most seriously weakens the argument above?

A．Students who most frequently remembered that they were in pain as children were no more likely than the average student to experience common pains very frequently.

B．Parents who were frequently in pain when their children were growing up often experience just as much pain after their children have grown up.

C．College students are in general less susceptible to common pains, like headaches, than are older adults.

D．Adult memories of the circumstances of childhood pain are often vivid, but adults can rarely recall the subjective experience of being in pain as a child.

E．A person"s adult recollections of childhood are likely to emphasize those memories that reflect the person"s adult experiences.

than limit the number of people they hire, trading firms aim to hire all those applicants who are able to be successful and to reject the rest. By this standard Quinsey-Leerheims record is perfect. All of its entry-level hirees over the past decade have become successful commodity traders. Which of the following, if true, would cast the most doubt on the assessment given above of Quinsey-Leerheim s hiring performance?

A．Over the past decade, Quinsey-Leerheim"s trading practices and policies have changed in a way that gives much more responsibility to individual traders.

B．Since the pool of entry-level applicants is mostly the same for all commodity-trading firms, Quinsey-Leerheim often competes with other trading firms for the strongest applicants.

C．Quinsey-Leerheim rejects some entry-level applicants who go on to become extremely successful commodity traders with other trading firms.

D．Commodity trading requires skills that are needed in very few other occupations, so that trading firms" hiring procedures typically differ significantly from those of other financial firms.

E．Commodity trading is very stressful, and even successful commodity traders rarely work as traders for longer than ten years, although they often earn substantial sums in those years.