The level of lead contamination in United States riv-ers declined between 1975 and 1985. Federal regula- tions requiring a drop in industrial discharges of lead went into effect in 1975, but the major cause of the decline was a 75 percent drop in the use of leaded gasoline between 1975 and 1985. Which of the following, if true, best supports the claim that the major cause of the decline in the level of lead contamination in United States rives was the decline in the use of leaded gasoline?
(A) The level of lead contamination in United States rivers fell sharply in both 1975 and 1983.
(B) Most of the decline in industrial discharges of lead occurred before 1976, but the largest
decline in the level of river contamination occurred between 1980 and 1985.
(C) Levels of lead contamination in rivers fell sharply in 1975-1976 and rose very slightly
over the next nine years.
(D) Levels of lead contamination rose in those rivers where there was reduced river flow due to drought.
(E) Although the use of leaded gasoline declined 75 percent between 1975 and1985, 80 percent
of the decline took place in 1985.

Since 1975 there has been in the United States a dra- matic decline in the incidence of traditional childhood diseases such as measles. This decline has been accom- panied by an increased incidence of Peterson’s disease, a hitherto rare viral infection, among children. Few
adults, however, have been affected by the disease. Which of the following, if true, would best help to explain the increased incidence of Peterson’s disease among children?
(A) Hereditary factors determine in part the degree to which a person is susceptible to the virus
that causes Peterson’s disease.
(B) The decrease in traditional childhood diseases and the accompanying increase in Peterson’s
disease have not been found in any other country.
(C) Children who contract measles develop an immunity to the virus that causes Peterson’s
disease.
(D) Persons who did not contract measles in child- hood might contract measles in adulthood, in
which case the consequences of the disease would generally be more severe.
(E) Those who have contracted Peterson’s disease are at increased risk of contracting chicken pox.

Cable-television spokesperson: Subscriptions to cable television are a bargain in comparison to “free” television. Remember that “free” televi- sion is not really free. It is consumers, in the end, who pay for the costly advertising that supports “free” television.

Which of the following, if true, is most damaging to the position of the cable-television spokesperson?

(A) Consumers who do not own television sets are less likely to be influenced in their purchasing decisions by television advertising than are consumers who own television sets.
(B) Subscriptions to cable television include access to some public-television channels, which do not accept advertising.
(C) For locations with poor television reception, cable television provides picture quality superior to that provided by free television.
(D) There is as much advertising on many cable television channels as there is on “free” television channels.
(E) Cable-television subscribers can choose which channels they wish to receive, and the fees vary accordingly

The wild mouflon sheep of the island of Corsica are direct descendants of sheep that escaped from domestication on the island 8,000 years ago. They therefore provide archaeologists with a picture of what some early domesticated sheep looked like, before the deliberate selective breeding that produced modern domesticated sheep began. The argument above makes which of the following assumptions?

(A) The domesticated sheep of 8,000 years ago were quite dissimilar from the wild sheep of the
time.
(B) There are no other existing breeds of sheep that escaped from domestication at about the
same time as the forebears of the mouflon.
(C) Modern domesticated sheep are direct descen- dants of sheep that were wild 8,000 years ago.
(D) Mouflon sheep are more similar to their fore- bears of 8,000 years ago than modern domes-
ticated sheep are to theirs.
(E) The climate of Corsica has not changed at all in the last 8,000 years.

Manager: Accounting and Billing are located right next to each other and the two depart-
ments do similar kinds of work; yet expenditures for clerical supplies charged
to Billing are much higher. Is Billing wasting supplies? Head of Billing: Not at all. Which of the following, if true, best supports the position of the Head of Billing?

(A) There are more staff members in Accounting than in Billing.
(B) Two years ago, expenditures in Accounting for clerical supplies were the same as were expen-
ditures that year in Billing for clerical supplies.
(C) The work of Billing now requires a wider vari- ety of clerical supplies than it did in the past.
(D) Some of the paper-and-pencil work of both Accounting and Billing has been replaced by
work done on computers.
(E) Members of Accounting found the clerical- supplies cabinet of Billing more convenient to
go to for supplies than their own depart- ment’s cabinet.

In a study of the effect of color on productivity, 50 of 100 factory workers were moved from their
drab workroom to a brightly colored workroom. Both these workers and the 50 who remained in the
drab workroom increased their productivity, proba- bly as a result of the interest taken by researchers in the work of both groups during the study. Which of the following, if true, would cast most doubt upon the author’s interpretation of the study results given above?

(A) The 50 workers moved to the brightly colored room performed precisely the same manufac-
turing task as the workers who remained in the drab workroom.
(B) The drab workroom was designed to provide adequate space for at most 65 workers.
(C) The 50 workers who moved to the brightly colored workroom were matched as closely
as possible in age and level of training to the 50 workers who remained in the drab work-room.
(D) Nearly all the workers in both groups had volunteered to move to the brightly colored
workroom.
(E) Many of the workers who moved to the brightly colored workroom reported that
they liked the drab workroom as well as or better than they liked the brightly colored
workroom.

Human beings can see the spatial relations among objects by processing information conveyed by light. Scientists trying to build computers that can detect spatial relations by the same kind of process have so far designed and built stationary machines. However, these scientists will not achieve their goal until they produce such a machine that can move around in its environment.
Which of the following, if true, would best support the prediction above?

(A) Human beings are dependent on visual cuesform motion in order to detect spatial relations.
(B) Human beings can often easily detect the spatial relations among objects, even when those
objects are in motion.
(C) Detecting spatial relations among objects requires drawing inferences from the infor-
mation conveyed by light.
(D) Although human beings can discern spatia relations through their sense of hearing,
vision is usually the most important means of detecting spatial relations.
(E) Information about the spatial relations among objects can be obtained by noticing such
things as shadows and the relative sizes of objects.

Consumer income reports produced by the govern- ment distinguish between households and families by means of the following definition: “A family is a household containing a householder and at least one person related to the householder.” Except for the homeless and people in group living quarters, most people live in households. According to the definition above, which of the
following must be true?
(A) All householders are members of families.
(B) All families include a householder.
(C) All of the people related to a householder form a family.
(D) Some people residing in group living quarters are members of families.
(E) Some homeless people reside in group livingquarters

The country of Maravia has severe air pollution, 80 percent of which is caused by the exhaust fumes of cars. In order to reduce the number of cars on the road, the government is raising taxes on the cost of buying and running a car by 20 percent. This tax increase, therefore, will significantly reduce air pollu- tion in Maravia. Which of the following, if true, most seriously
weakens the argument above?

(A) The government of Maravia is in the process ofbuilding a significant number of roadways.
(B) Maravia is an oil-producing country and is ableto refine an amount of gasoline sufficient for
the needs of its population.
(C) Maravia has had an excellent public transporta- tion system for many years.
(D) Ninety percent of the population of Maravia is very prosperous and has a substantial
amount of disposable income.
(E) In Maravia, cars that emit relatively low levels of pollutants cost 10 percent less to operate,
on average, than do cars that emit high levels of pollutants

Despite the approach of winter, oil prices to indus- trial customers are exceptionally low this year and likely to remain so. Therefore, unless the winter is especially severe, the price of natural gas to indus- trial customers is also likely to remain low. Which of the following, if true, provides the most support for the conclusion above?

(A) Long-term weather forecasts predict a mild winter.

(B) The industrial users who consume most natural gas can quickly and cheaply switch to using
oil instead.
(C) The largest sources of supply for both oil and natural gas are in subtropical regions unlikely
to be affected by winter weather.
(D) The fuel requirements of industrial users of nat- ural gas are not seriously affected by the
weather.
(E) Oil distribution is more likely to be affected by severe winter weather than is the distribution
of natural gas.

Ms. Ingres has filed a lawsuit against the firm claiming that she is the victim of gender-based discrimination because she was not promoted to partner. The firm has reviewed her personnel records and concluded that she had an excellent work record that was superior to the records of several men with fewer years of service who were promoted to partner. Additionally, there are no negative entries in her file. Nonetheless, we feel justified in refusing to make her a partner because this lawsuit shows that she is not a team player.

The reasoning of the speaker is most similar to which of the following?

(A) An elected official who is charged with corruption but refuses to resign from office pending a full investigation into the matter

(B) A contractor who acknowledges that faulty materials were used in a building but claims that he was defrauded by a supplier

(C) A young man who admits killing both of his parents who pleads for a judge to show him mercy because he is an orphan

(D) A teacher who gives a student a failing mark on a term paper after the student admits to plagiarizing the paper

(E) A soldier who refuses to follow orders from a superior officer and argues that the orders were immoral and therefore invalid

In the United States, injuries to passengers involved in automobile accidents are typically more severe than in Europe, where laws require a different kind of safety belt. It is clear from this that the United States needs to adopt more stringent standards for safety belt design to protect automobile passengers better.Each of the following, if true, weakens the argument above EXCEPT:

(A) Europeans are more likely to wear safety belts than are people in the United States.
(B) Unlike United States drivers, European drivers receive training in how best to react in the
event of an accident to minimize injuries to themselves and to their passengers.
(C) Cars built for the European market tend to have more sturdy construction than do cars
built for the United States market.
(D) Automobile passengers in the United States have a greater statistical chance of being
involved in an accident than do passengers in Europe.
(E) States that have recently begun requiring the European safety belt have experienced no
reduction in the average severity of injuries suffered by passengers in automobile accidents.

A company’s personnel director surveyed employees about their satisfaction with the company’s system for awarding employee performance ratings. The survey data indicated that employees who received high ratings were very satisfied with the system. The personnel director concluded from these data that the company’s best-performing employees liked the system.
The personnel director’s conclusion assumes which of the following?

(A) No other performance rating system is as good as the current system.
(B) The company’s best-performing employees received high ratings.
(C) Employees who received low ratings were dissatisfied with the system.
(D) Employees who receive high ratings from a performance-rating system will like that system.
(E) The company’s best-performing employees were motivated to perform well by the knowledge
that they would receive performance ratings.

Less than 50 percent of a certain tropical country’s wildlands remains intact. Efforts are under way to restore biological diversity in that country by restoring some destroyed wild habitats and extending some relatively intact portions of forests. However, opponents argue that these efforts are not needed because there is still plenty of wildland left.

Which of the following, if true, most significantly weakens the argument of the opponents of conservation efforts?

(A) As much, if not more, effort is required to restore a wild habitat as to preserve an intact habitat.
(B) The opponents of restoration efforts are, for the most part, members of the wealthier classes in their own villages and cities.
(C) Existing conservation laws have been very effective in preserving biological diversity within the wildlands that remain intact.
(D) For many tropical species native to that country, the tropical wildlands that are still relatively intact do not provide appropriate habitats for reproduction.
(E) If a suitable population of plants and animals is introduced and is permitted to disperse and grow, tropical habitats can most certainly be restored.

Exports of United States wood pulp will rise consid-erably during this year. The reason for the rise isthat the falling value of the dollar will make itcheaper for paper manufacturers in Japan and West-ern Europe to buy American wood pulp than to getit from any other source.Which of the following is an assumption made indrawing the conclusion above?

(A) Factory output of paper products in Japan andWestern Europe will increase sharplyduringthisyear.
(B) The quality of the wood pulp produced in theUnited States would be adequate for the
purposes of Japanese and Western Europeanpaper manufacturers.
(C) Paper manufacturers in Japan and WesternEurope would prefer to use wood pulp
produced in the United States if cost werenot a factor.
(D) Demand for paper products made in Japan andWestern Europe will not increase sharply
during this year.
(E) Production of wood pulp by United Statescompanies will not increase sharply duringthis year.

A manufacturer of men’s dress socks sought to increase profits by increasing sales. The size of its customer pool was remaining steady, with the average customer buying twelve pairs of dress socks per year. The company’s plan was to increase the number of promotional discount-sale periods to one every six months.Which of the following, if it is a realistic possibility, casts the most serious doubt on the viability of the company’s plan?

(A) New manufacturing capacity would not be required if the company were to increase the number of pairs of socks sold.
(B) Inventory stocks of merchandise ready for sale would be high preceding the increase in the number of discount sale periods.
(C) The manufacturer’s competitors would match its discounts during sale periods, and its
customers would learn to wait for those times to make their purchases.
(D) New styles and colors would increase customers’ consciousness of fashion in dress
socks, but the customers’ requirements for older styles and colors would not be reduced.
(E) The cost of the manufacturer’s raw materials would remain steady, and its customers
would have more disposable income.

A study comparing a group of chronically depressed individuals with an otherwise matched group of individuals free from depression found significantly more disorders of the immune system among the depressed group. According to the researchers, these results strongly support the hypothesis that mental states influence the body’s vulnerability to infection.

Which of the following, if true, casts the most serious doubt on the researchers’ interpretation of their findings?

(A) The researchers’ view does little more than echo a familiar theme in folklore an literature.
(B) Chronically depressed individuals are no less careful than others to avoid exposure to
infections.
(C) Disorders of the immune system cause many of those individuals who have them to become chronically depressed.
(D) Individuals who have previously been free from depression can become depressed quite suddenly.
(E) A high frequency of infections can stem from an unusually high level of exposure rather than from any disorder of the immune system.

Bill: The newspaper discontinued Dr. Andrews’ weekly humor column because the editor said that he had plagiarized the work of another humorist. Dr. Andrews explained, however, that much of the column’s material was from stories submitted by readers and that he had no idea that the offending items had been written by another humorist. Since his use of the items was innocent, Dr. Andrews’ column should be reinstated.

Kathy: That’s not the point. No one accused Dr. Andrews of violating another author’s copyright. The offense was that he passed off material as his own that he had not actually written. And so it was plagiarism even though the owner of the copyrighted material wrote to the newspaper to say that he did not think that Dr. Andrews had intentionally stolen from him.

Which one of the following principles best justifies Bill’s defense of Dr. Andrews?

(A) A writer can quote without attribution if it appears that the material is in common circulation.

(B) An author is entitled to quote without attribution if the copyright owner will later grant permission.

(C) A humorist can retell anecdotes submitted by readers only after doing a thorough search for the source.

(D) An author has an absolute right to quote hers or his previously published work without need of attribution.

(E) Literary works that are no longer under copyright protection can be freely quoted by any writer.

Previous studies have indicated that eating chocolate increases the likelihood of getting heart disease. However, a new, more reliable study has indicated
that eating chocolate does not increase the likelihood of getting heart disease. When the results of the new study become known, consumption of
chocolate will undoubtedly increase.

Which of the following is an assumption on which the conclusion above is based?

(A) Most people who eat a great deal of chocolate will not get heart disease.
(B) Although they believe that eating chocolate increases the likelihood of getting heart disease, some people still eat as much chocolate as they want.
(C) People who have heard that eating chocolate increases the likelihood of getting heart disease do not believe it.
(D) There are people who currently eat as much chocolate as they want because they have not heard that eating chocolate increases the likelihood of getting heart disease.
(E) There are people who currently limit their consumption of chocolate only because they believe that eating chocolate increases the likelihood of getting heart disease.