Strengthen/Weaken
The ivory-billed woodpecker has been considered extinct for the past several decades. Recently, researchers claim to have found a pair of ivory-billed woodpeckers in Arkansas. Their best evidence is a video that shows a large woodpecker flying away from the camera. The bird has the characteristic large white patches on the trailing edge of the wings. This is one of the factors that distinguishes ivory-billeds from the closely related pileated woodpecker. However, skeptics of the discovery argue that some abnormal pileateds can have extra white on the wing and that the bird in the video is most likely an abnormal pileated. They conclude that the ivory-billed has not been found and is still extinct.
Which of the following, if true, most strengthens the skeptics' reasoning that the ivory-billed woodpecker is still extinct?
A. Before this discovery, the last reported ivory-billed woodpeckers were seen in Louisiana.
B. The first person to discover the ivory-billed woodpeckers was not a specialist, but professional ornithologists were soon brought in to confirm the identification.
C. In the same area where the video was shot, researchers also heard the distinctive double-tap used by ivory-billed woodpeckers.
D. Of the five key field marks that identify ivory-billed woodpeckers, only the extra white on the wings has been seen, and this is also the only feature that occurs on abnormal pileated woodpeckers.
E. The bird in the video is clearly seen using the shallow wing beats of the ivory-billed woodpecker rather than the deeper wing beats of the abnormal pileated woodpecker.
D. Of the five key field marks that identify ivory-billed woodpeckers, only the extra white on the wings has been seen, and this is also the only feature that occurs on abnormal pileated woodpeckers.
Some scholars of mythology claim that myths exist to explain natural phenomena; for example, the myth of Zeus's casting lightning bolts from heaven helped the ancient Greeks explain an otherwise unexplainable event. Other scholars argue that myths are a way in which people explore psychological phenomena, such as a son's feelings toward his mother. If these various scholars are correct, then all myths can be interpreted both as explanations of natural events and explorations of psychology.
This argument is most vulnerable to criticism on the grounds that it
A. draws a conclusion about myths that has already been discounted by experts in the field
B. takes for granted that the myths of ancient people are relevant today
C. imposes a modern, western sensibility on the myths of pre-modern people from a variety of cultures
D. criticizes scholars who insist that one or the other interpretation of myths must be correct
E. assumes that what is true of myths in general must also be true of each individual myth
E. assumes that what is true of myths in general must also be true of each individual myth
American citizens believe that they live in a democracy. In presidential elections, though, citizens do not get to vote for president. They can only choose electors who cast votes for president on behalf of entire states. Therefore, Americans do not actually live in a democracy.
Which one of the following exhibits a pattern of reasoning most similar to the one in the argument presented here?
A. Most colleges have student government. All students are allowed to vote in student government elections. In fact, though, very few students vote or take any interest in student government affairs. Therefore, student government serves no useful purpose.
B. All cities have local law enforcement programs. Usually, the police handle crime in the city, the sheriff's department handles county matters, and the state police handle matters that affect the entire state. Therefore, most cities have too much duplication of law enforcement jobs.
C. The United States is said to have a free market economy. In fact, though, the U.S. economy is heavily regulated by the government, which gives many advantages to large businesses and punishes small companies and the self-employed. Therefore, the United States does not really have a free market economy.
D. Most teachers believe that education courses are valuable. Many colleges and universities, on the other hand, look down on education degrees. Therefore, future teachers should not major in education.
E. Most health insurers claim to offer their customers a variety of choices in health care. Doctors, however, do not post a menu of prices for customers to peruse before accepting treatment, and patients in hospitals do not get to choose the doctors who treat them. Therefore, health insurers are dishonest.
C. The United States is said to have a free market economy. In fact, though, the U.S. economy is heavily regulated by the government, which gives many advantages to large businesses and punishes small companies and the self-employed. Therefore, the United States does not really have a free market economy.
Dermatologist: Many people believe that they can prevent acne by using clay masks to draw impurities from pores and applying toner, which they think will close pores and prevent dirt from getting into them. If this were true, then acne would be very easy to treat with topical measures. In fact, acne blemishes develop within the skin itself and are affected by internal factors such as hormones and sebum. Therefore, using external measures such as masks and toners is useless.
The dermatologist's conclusion requires the assumption that
A. clay masks can dry out the skin
B. some people like the sensation of toners on their skin
C. dirt on the skin does not cause acne
D. doctors have successfully treated acne with oral antibiotics
E. most dermatologists recommend that patients clean their faces with gentle soap instead of harsh cleansers
C. dirt on the skin does not cause acne
A cosmetics company did a study of hair colors involving 100 women, all of whom dyed their hair with the same product. Half of them then washed their hair with special shampoo made for color-treated hair, and half of them washed their hair with ordinary shampoo. After two months, there was no difference in color fading between the two groups. Therefore, shampoo for color-treated hair is valueless.
Which one of the following statements, if true, most seriously weakens the argument?
A. Most shampoos contain the same basic ingredients, such as sodium lauryl sulfate or sodium laureth sulfate.
B. Most hair experts recommend touching up hair color every four to six weeks.
C. Both groups had equal numbers of women in their 30s, 40s, and 50s, with comparable natural hair colors.
D. The women who had used shampoo for color-treated hair had softer and shinier hair than the women who used ordinary shampoo.
E. Hair color technology has improved tremendously in the last ten years, making it possible for all women to successfully color their hair at home.
D. The women who had used shampoo for color-treated hair had softer and shinier hair than the women who used ordinary shampoo.
I bought a pair of glasses from an optometrist. One of the lenses regularly pops out of the frame. Therefore, this optometrist does not know how to make a good pair of glasses.
The reasoning in the argument is most vulnerable to criticism on the grounds that the argument
A. does not allow the optometrist a chance to defend himself
B. does not consider the possibility that other optometrists also make defective frames
C. criticizes the optometrist's use of a particular technique when making glasses
D. jumps to the conclusion that the defect in the glasses must be due to the optometrist's lack of skill
E. accuses the optometrist of deliberately sabotaging the glasses
D. jumps to the conclusion that the defect in the glasses must be due to the optometrist's lack of skill
People usually meet expectations. Thus, if Person A informs Person B that he or she is expected to perform a particular duty and Person B accepts that duty, generally, Person B will perform the duty as expected.
Which one of the following best illustrates this proposition?
A. A teacher informs a girl that she is responsible for feeding the class hamster every morning, and the girl agrees to do this. After this, the girl feeds the hamster every morning without the teacher telling her to.
B. A partner asks an associate to write a memo on a legal issue. Because the associate is inexperienced, the partner supervises his work closely and helps him write several drafts of the memo.
C. Country A has agreed to be Country B's military ally. Country A then elects a new president who disagrees with Country B's policies, and when Country B goes to war, Country A refuses to help.
D. A coach teaches his players a particular strategy. The first time they use it in a game, they win. Thereafter, they go on to win the league championship.
E. A psychologist tells a patient that behavior modification will help her quit smoking. The patient follows the program designed by the psychologist and quits smoking successfully.
A. A teacher informs a girl that she is responsible for feeding the class hamster every morning, and the girl agrees to do this. After this, the girl feeds the hamster every morning without the teacher telling her to.
Gynecologist: Scottish researchers have developed a test that allows them to predict at what age a woman will experience menopause. The scientists use a model that compares a woman's ovaries to "average" ovaries to see whether her ovaries are aging faster or more slowly than average. They have discovered that the size of ovaries is directly related to the number of eggs they contain, which in turn is directly related to fertility. This discovery will significantly influence women's decisions on when to have children.
The gynecologist's conclusion follows logically if which one of the following is assumed?
A. Women with smaller ovaries tend to have less success with assisted reproduction techniques, such as in vitro fertilization.
B. Most women experience menopause around the age of 50, but their fertility starts to decline at the age of 37.
C. Any discovery that allows women to predict when they will experience menopause will influence their decisions on when to have children.
D. The test cannot tell women how likely they are to conceive in the years just prior to menopause.
E. Every woman is born with several million eggs in her ovaries, which formed while she was a fetus; the number of eggs dwindles over her lifetime, until at menopause she has 1,000 or fewer.
C. Any discovery that allows women to predict when they will experience menopause will influence their decisions on when to have children.
Snakes exist on every continent except for Antarctica, which is inhospitable to all cold-blooded animals. The continent of Australia is home to many of the deadliest snakes in the world. However, the nearby island nation of New Zealand has no snakes at all. Scientists estimate that snakes originated about 100 million years ago when the continents were joined and the snakes stayed on the main land masses of the continents when they split apart. Thus snakes are absent from New Zealand because they are unable to swim and therefore could not make the journey.
Which of the following, if true, would most strengthen this argument?
A. Snakes are found on many other islands of the Pacific Ocean.
B. Snakes are found in South America at latitudes farther south than New Zealand.
C. Islands like Hawaii and New Zealand are very aggressive about preventing an accidental introduction of snakes.
D. Sea snakes can swim and are present in the warmer oceans of the world.
E. Snakes are also absent from other major islands, such as Hawaii, Ireland, and Greenland.
E. Snakes are also absent from other major islands, such as Hawaii, Ireland, and Greenland.
School board member: A school in a wealthy suburb and a school in a poverty-stricken part of the inner city received exactly the same funding and got completely different results. The school in the suburb sent all its graduates to college, but the school in the city sent only 10 percent to college and suffered a 25 percent dropout rate before graduation. Clearly, the inner-city school is wasting its money, whereas the suburban school puts its money to good use.
The reasoning in the school board member's argument is flawed because the argument
A. mistakenly finds a correlation between levels of funding and graduation rates
B. assumes that most of the inner-city school students are unprepared for college
C. fails to consider that funding levels are not the only factors influencing school performance
D. unfairly criticizes the administrators of the inner-city school for their students' failures
E. jumps to the conclusion that students in the suburbs are more intelligent and harder working than students in the inner city
C. fails to consider that funding levels are not the only factors influencing school performance
Shoe company: Our shoes are masterpieces of podiatric design. We use wide toe boxes to give toes room to spread naturally. Our foot beds support the entire foot, toe, arch, and heel. Slightly raised heels and a curved sole alleviate fatigue and facilitate walking. The materials we use in soles are excellent shock absorbers. We guarantee that your feet will love our shoes or your money back.
The claim that "we guarantee that your feet will love our shoes or your money back" plays which one of the following roles?
A. It infers from the information preceding it that advanced podiatric design is essential to comfortable shoes.
B. It implies that if a consumer purchases these shoes and they hurt her feet, the company will refund her purchase price.
C. It suggests that all customers who buy these shoes are satisfied with their purchases.
D. It criticizes the design of most mass-produced shoes, which are much more likely to cause foot problems.
E. It argues that only shoes designed by certified podiatrists can guarantee healthy and pain-free feet.
B. It implies that if a consumer purchases these shoes and they hurt her feet, the company will refund her purchase price.
Bullying bosses are a common fixture of the workplace. They usually abuse subordinates simply because they enjoy exerting power for its own sake. Subordinates who are abused by their bosses typically perform their jobs as usual and almost never lodge formal complaints, preferring to complain in sessions with co-workers during which they discuss their bosses' misdeeds.
Which one of the following best illustrates this proposition?
A. Boss Maureen blames subordinate Skylar for all her mistakes, informing clients that she would have gotten work done on time but for his incompetence. Skylar files a complaint with the Equal Employment Opportunity Commission and receives a right-to-sue letter for national origin discrimination.
B. Boss Frank makes subordinate David stay late every afternoon, making him do work that he could have done in the morning if he had known about it. David tolerates this for a few months and then accepts a job at a rival company.
C. Boss Belinda makes fun of the way subordinate Casey dresses, telling her that no one will ever take her seriously with her budget wardrobe. Casey informs her company's human resources manager of Belinda's comments and is transferred to another department.
D. Boss Bill requires that subordinate Paul bill a certain number of hours but often fails to provide Paul with enough work. Paul comes to the office every day and pretends to work without accomplishing very much, spending much of his time complaining about Bill to his secretary.
E. Boss Stephanie constantly criticizes subordinate Kim's work, correcting it one way one day and then correcting it back to its original state the next. Kim meekly accepts the criticisms but spends every Thursday evening at a bar with co-workers making fun of Stephanie.
E. Boss Stephanie constantly criticizes subordinate Kim's work, correcting it one way one day and then correcting it back to its original state the next. Kim meekly accepts the criticisms but spends every Thursday evening at a bar with co-workers making fun of Stephanie.
DOUBLE JEOPARDY All worker bees are female and have no sense of themselves as individuals. They instead live to further the welfare of the queen and her hive as a whole, helping her to lay eggs and raising her offspring. This means that workers spend their lives helping the queen to pass on her genetic traits and fail to pass on their own genes to offspring.
Which one of the following statements, if true, most seriously weakens this argument?
A. All the bees in a hive are related to one another.; the workers are all sisters and the quen is their mother. There is no need for workers to pass on their own genes because they are furthering their mother's line.
B. When a hive loses its queen, some workers develop the ability to lay eggs; these unfertilized eggs can hatch only into male drones.
C. A bee colony has only one queen at a time. When a new queen hatches in a hive, she immediately seeks out all other queens and tries to kill them or drive them out.
D. If a beekeeper can catch the queen from a swarm, he can install her in a beehive, and the entire swarm of worker bees will immediately move into the hive with her.
E. Queen bees mate once in their lives and store sperm from this mating to fertilize all their worker eggs. Male drones hatch from unfertilized eggs.
B. When a hive loses its queen, some workers develop the ability to lay eggs; these unfertilized eggs can hatch only into male drones.
Motorcyclists are told always to wear helmets when they ride their motorcycles. But helmets only protect riders when they have wrecks, and wrecks occur only once out of every 1,000 rides. Therefore, a motorcyclist would be perfectly safe if he wore his helmet only once out of every 1,000 rides.
Which one of the following employs a flawed argumentative strategy that is most closely parallel to the flawed argumentative strategy in this statement?
A. My European client calls once a week, always in the evening, after everyone has left the office. I will be sure to get his messages if I turn on my telephone's answering machine once a week.
B. This sunscreen allows me to stay in the sun 15 times longer than I could without sunscreen. If I apply two coats of it, it will allow me to stay in the sun 30 times longer.
C. The odds are 1,000 to 1 against winning the big jackpot on this slot machine. If I play the slot machine 1,000 times, I am sure to win the big jackpot.
D. Seat belts protect passengers in automobile accidents, but accidents only occur in one out of every 2,000 car trips. Because drivers are in the car the most, they should wear their seat belts most often.
E. Top law schools accept one out of every 20 applicants. Therefore, someone who wants to get into a top law school should apply to 20 of them.
A. My European client calls once a week, always in the evening, after everyone has left the office. I will be sure to get his messages if I turn on my telephone's answering machine once a week.
Traveler: When I flew to Boston on Tuesday, I checked my suitcase but carried my computer on the plane. When I arrived at Logan Airport, none of the checked bags from the flight had arrived. The baggage office clerk was very helpful with my polite questions but punished the other passengers who were so rude by making them wait for her assistance.
Which one of the following principles is best illustrated by the traveler's reasoning?
A. A stitch in time saves nine.
B. Do not price an unborn calf.
C. Do not put all your eggs in one basket.
D. Neither a borrower nor a lender be.
E. You catch more flies with honey than you do with vinegar.
E. You catch more flies with honey than you do with vinegar.
History has shown that people will reduce their consumption of fuel only if they have a financial incentive to do so. For example, in the energy crisis of the 1970s, people drastically lowered their consumption of gasoline. When California suffered its own statewide energy crisis in 2001, the state promised a 20 percent discount on power bills to consumers who reduced their power consumption, and a majority of citizens managed this feat. The government should therefore implement financial incentives to reduce energy consumption, such as taxes on gasoline or rewards for reduced consumption.
Which one of the following is an assumption required by the argument?
A. The government should not interfere with energy policies and should instead let the market guide consumption.
B. In some cases, citizens have reduced their power consumption even without incentives.
C. Policies created during the energy crisis of the 1970s should serve as a model of policies that could address the current energy crisis.
D. Getting citizens to use less energy than they currently do is desirable.
E. The federal government should follow California's lead in setting energy policy.
D. Getting citizens to use less energy than they currently do is desirable.
To earn a graduate equivalency diploma, a student must pass tests on subjects taught in high schools, proving that he or she has mastered them to the degree assumed of a high school graduate. It makes sense for a student to drop out of high school and earn a GED. A GED takes much less time to earn than a high school diploma and provides evidence that the student has learned everything he or she would have learned in high school.
Which one of the following, if true, most seriously weakens the argument?
A. Some GED-prep programs incorporate enrichment activities into their test preparation, such as taking students to art exhibits and theatrical performances.
B. Most colleges and universities consider a GED equivalent to a high school degree for admission purposes.
C. Many successful businesspeople dropped out of high school and earned a GED.
D. Employers assume that high school graduates generally have a much higher level of mastery of academic subjects than those who earn GEDs.
E. Many GED students are slightly older than high school students, and they often hold jobs in addition to studying to pass the GED tests.
D. Employers assume that high school graduates generally have a much higher level of mastery of academic subjects than those who earn GEDs.
The phrase "under God" in the Pledge of Allegiance is not unconstitutional because, throughout our nation's history, various presidents and political leaders have invoked God in inaugural addresses, Thanksgiving speeches, and other public statements of national unity. Therefore, requiring public school teachers to lead their students in the pledge every day does not force religious beliefs on anyone.
The argument is most vulnerable to criticism on the grounds that it
A. ignores evidence that many politicians do not invoke God in public addresses because they believe it would be an improper exercise of religion
B. fails to acknowledge that the majority of U.S. citizens approve of including the phrase "under God" in the pledge
C. equates freedom of expression by national leaders with proof that requiring students to mention God in the pledge is not an unjust imposition of religious beliefs
D. praises teachers who lead their classes in the Pledge of Allegiance for performing an act of patriotism that deserves no reward
E. assumes that all U.S. citizens believe in the same deity and wish to invoke that deity's protection of the nation and its people
C. equates freedom of expression by national leaders with proof that requiring students to mention God in the pledge is not an unjust imposition of religious beliefs
The document was published under a license that allows others to copy it and disseminate it as long as they do so for noncommercial purposes only. Company A included copies of the document in a training manual that it marketed and sold, arguing that the license was invalid. However, even if the license were proved invalid, the copyright was still valid, leaving Company A with no rights to use the document in any way at all.
Which one of the following situations best demonstrates the principle illustrated by this argument?
A. The warranty on the laptop computer claimed to be rendered void if the user opened the case. But the manual that came with the laptop included instructions for opening the case to upgrade the computer's memory. Consumers successfully argued that those instructions constituted an endorsement of users' opening the case and that, therefore, the warranty was not void.
B. When the 13-year-olds were caught trying to enter an NC-17 movie at a multiplex, they argued that the cashier at the ticket counter had sold them tickets for that movie. The manager explained that the cashier's error did not change the rules of age limits and movie ratings.
C. A restaurant was fined by the Alcoholic Beverage Commission for serving distilled liquors when its license covered only beer and wine. The restaurant's manager argued that he had applied for the proper license and expected to receive it within days. The ABC countered that a license was valid only from the moment the restaurant posted it on the premises.
D. Ted's parents have stated that he cannot drive the station wagon unless it is to Alice's house. When his mother saw the station wagon parked at the mall, some miles away, Ted argued that Alice was not at home. Ted's mom pointed out that he ought, upon discovering that fact, to have driven straight home.
E. The celebrity sued the magazine for publishing photographs of him sunning himself in his backyard, which was enclosed by a high fence. The magazine claimed that he was a public figure and did not, therefore, have the same rights to privacy as normal citizens. The celebrity claimed that the extensive fence around his yard justified his privacy rights when behind it, despite his prominent stature in the eyes of the public.
D. Ted's parents have stated that he cannot drive the station wagon unless it is to Alice's house. When his mother saw the station wagon parked at the mall, some miles away, Ted argued that Alice was not at home. Ted's mom pointed out that he ought, upon discovering that fact, to have driven straight home.
Career counselor: Many large international companies have changed their practices regarding international assignments. They are placing much more emphasis on helping spouses of expatriate employees to adjust to the foreign environment. This has reduced premature returns by 67 percent.
Which one of the following is an assumption upon which the career counselor's argument depends?
A. Spousal and marital difficulties were formerly responsible for a large number of premature returns from foreign assignments.
B. When an employee is placed in a foreign assignment for a year or less, his or her family sees the assignment as an adventure.
C. Expatriate employees work long hours and travel a great deal, and their children make new friends at school, but spouses often have no friends and no work to support them while they're abroad.
D. The majority of international assignments today last for less than a year, but ten years ago, 70 percent of them lasted much longer than one year.
E. Many companies now offer expatriate spouses language training, career guidance, and assistance in finding homes and schools.
A. Spousal and marital difficulties were formerly responsible for a large number of premature returns from foreign assignments.