Concept Article - What can indeed strengthen an argument?

Normally a strengthener is

1. An agreeing survey result or a finding that goes on similar lines of the premise

Wood smoke contains dangerous toxins that cause changes in human cells. Because wood smoke presents such a high health risk, legislation is needed to regulate the use of open-air fires and wood-burning stoves.

Which of the following, if true, provides the most support for the argument above?

(A) The amount of dangerous toxins contained in wood smoke is much less than the amount contained in an equal volume of automobile exhaust.
(B) Within the jurisdiction covered by the proposed legislation, most heating and cooking is done with oil or natural gas.
(C) Smoke produced by coal-burning stoves is significantly more toxic than smoke from wood burning stoves.
(D) No significant beneficial effect on air quality would result if open-air fires were banned within the jurisdiction covered by the proposed legislation.
(E) In valleys where wood is used as the primary heating fuel, the concentration of smoke results in poor air quality.

The conclusion that legislation is needed to regulate the use of open-air fires and wood-burning stove is drawn from the premise that such smoke is hazardous to health. Here choice E expresses the fact that in valleys where wood is used as the primary heating fuel, the concentration of smoke results in poor air quality. This goes along with the premise hence this support the conclusion

2. A reasonable prediction that is bound to come true

In Washington County, attendance at the movies is just large enough for the cinema operators to make modest profits. The size of the county’s population is stable and is not expected to increase much. Yet there are investors ready to double the number of movie screens in the county within fi vet years, and they are predicting solid profits both for themselves and for the established cinema operators.

Which of the following, if true about Washington County, most helps to provide a justification for the investors’ prediction?

(A) Over the next ten years, people in their teenage years, the prime movie going age, will be a rapidly growing proportion of the county’s population.
(B) As distinct from the existing cinemas, most of the cinemas being planned would be located in downtown areas, in hopes of stimulating an economic revitalization of those areas.
(C) Spending on video purchases, as well as spending on video rentals, has been increasing modestly each year for the past ten years.
(D) The average number of screens per cinema is lower among existing cinemas than it is among cinemas still in the planning stages.
(E) The sale of snacks and drinks in cinemas accounts for a steadily growing share of most cinema operators’ profits.

Here we assume that in the next decade the future population especially those who will be teenagers are likely to be frequent movie-goers and hence this assumption as held out in Choice A helps to strengthen the conclusion

3. A cause that has only one effect

Springfield Fire Commissioner: The vast majority of false fire alarms are prank calls made anonymously from fire alarm boxes on street corners. Since virtually everyone has access to a private telephone, these alarm boxes have outlived their usefulness. Therefore, we propose to remove the boxes. Removing the boxes will reduce the number of prank calls without hampering people’s ability to report a fire.

Which of the following, if true, most strongly supports the claim that the proposal, if carried out, will have the announced effect?

(A) The fire department traces all alarm calls made from private telephones and records where they came from.
(B) Maintaining the fi re alarm boxes costs Springfield approximately $5 million annually.
(C) A telephone call can provide the fi re department with more information about the nature and size of a fire than can an alarm placed from an alarm box.
(D) Responding to false alarms significantly reduces the fi re department’s capacity for responding to fi res.
(E) On any given day, a significant percentage of the public telephones in Springfield are out of Service

Here, it is clear that the private phone can not dodge detection, therefore the removal of public phones will force the pranksters to use private phones and will be easily detected. Thus that the use of private call can result in only one effect strengthens the conclusion, which is brought out by choice A



Most employees in the computer industry move from company to company, changing jobs several times in their careers. However, Summit Computers is known throughout the industry for retaining its employees. Summit credits its success in retaining employees to its informal, non-hierarchical work environment.

Which of the following, if true, most strongly supports Summit’s explanation of its success in retaining employees?

(A) Some people employed in the computer industry change jobs if they become bored with their current projects.
(B) A hierarchical work environment hinders the cooperative exchange of ideas that computer industry employees consider necessary for their work.
(C) Many of Summit’s senior employees had previously worked at only one other computer company.
(D) In a non-hierarchical work environment, people avoid behavior that might threaten group harmony and thus avoid discussing with their colleagues any dissatisfaction they might have with their jobs.
(E) The cost of living near Summit is relatively low compared to areas in which some other computer companies are located.

Here, the argument says that the company retains its employees simply because of informal, non-hierarchical work environment. By implication it means that a hierarchical work environment hinders with the normal working of the employs and drives them to dissatisfaction, which is made clear by Choice B.


Here are some GMAT examples...........


1. The Plexis Corporation, a leading computer chip manufacturer, is currently developing a new chip, which is faster and more efficient than any computer chip currently in use. The new chip will be released for sale in twelve months. Plexis’ market research has shown that initial sales of the new chip would be maximized by starting to advertise it now, but the company has decided to wait another six months before doing so.

Which of the following, if true, provides the Plexis Corporation with the best reason for postponing advertising its new chip?

(A) Some computer users are reluctant to purchase new computer products when they are first released.
(B) The cost of an advertising campaign capable of maximizing initial sales of the new chip would be no greater than campaigns previously undertaken by Plexis.
(C) Advertising the new chip now will significantly decrease sales of Plexis’ current line of computer chips.
(D) Plexis’ major rivals in the computer chip manufacturing business are developing a chip with capabilities that are comparable to those of Plexis’ new chip.
(E) Taking full advantage of the capacities of the new chip will require substantial adjustments in other segments of the computer industry.



2. Many breakfast cereals are fortified with vitamin supplements. Some of these cereals provide 100 percent of the recommended daily requirement of vitamins. Nevertheless, a well-balanced breakfast, including a variety of foods, is a better source of those vitamins than are such fortified breakfast cereals alone.

Which of the following, if true, would most strongly support the position above?

(A) In many foods, the natural combination of vitamins with other nutrients makes those
vitamins more usable by the body than are vitamins added in vitamin supplements.
(B) People who regularly eat cereals fortified with vitamin supplements sometimes neglect to eat the foods in which the vitamins occur naturally.
(C) Foods often must be fortified with vitamin supplements because naturally occurring
vitamins are removed during processing.
(D) Unprocessed cereals are naturally high in several of the vitamins that are usually added to fortified breakfast cereals.
(E) Cereals containing vitamin supplements are no harder to digest than similar cereals without added vitamins.



3. The Eurasian ruffe, a fish species inadvertently introduced into North America’s Great Lakes in recent years, feeds on the eggs of Lake Whitefish, a native species, thus threatening the lakes’ natural ecosystem. To help track the ruffe’s spread, government agencies have produced wallet-sized cards about the ruffe. The cards contain pictures of the ruffe and explain the danger they pose; the cards also request anglers to report any ruffe they catch.

Which of the following, if true, would provide most support for the prediction that the agencies’ action will have its intended effect?

(A) The ruffe has spiny fins that make it unattractive as prey.
(B) Ruffe generally feeds at night, but most recreational fishing on the Great Lakes is done during daytime hours.
(C) Most people who fish recreationally on the Great Lakes are interested in the preservation of the lake whitefish because it is a highly prized game fish.
(D) The ruffe is one of several nonnative species in the Great Lakes whose existence threatens the survival of Lake Whitefish populations there.
(E) The bait that most people use when fishing for whitefish on the Great Lakes is not attractive to ruffe.



4. In Swartkans territory, archaeologists discovered charred bone fragments dating back one million years. Analysis of the fragments, which came from a variety of animals, showed that they had been heated to temperatures no higher than those produced in experimental campfires made from branches of white stinkwood, the most common tree around Swartkans.

Which of the following, if true, would, together with the information above, provide the best basis for the claim that the charred bone fragments are evidence of the use of fire by early hominids?

(A) The white stinkwood tree is used for building material by the present-day inhabitants of Swartkans.
(B) Forest fires can heat wood to a range of temperatures that occur in campfires.
(C) The bone fragments were fitted together by the archaeologists to form the complete skeletons of several animals.
(D) Apart from the Swartkans discovery, there is reliable evidence that early hominids used fire as many as 500,000 years ago.
(E) The bone fragments were found in several distinct layers of limestone that contained primitive cutting tools known to have been used by early hominids.

Hint: An agreeing survey result or a finding that goes on similar lines of the premise



5. Male bower birds construct elaborately decorated nests, or bowers. Basing their judgment on the fact that different local populations of bowerbirds of the same species build bowers that exhibit different building and decorative styles, researchers have concluded that the bowerbirds’ building styles are a culturally acquired, rather than a genetically transmitted trait.

Which of the following, if true, would most strengthen the conclusion drawn by the researchers?

(A) There are more common characteristics than there are differences among the bower-building styles of the local bowerbird population that has been studied most extensively.
(B) Young male bowerbirds are inept at bower building and apparently spend years watching their elders before becoming accomplished in the local bower style.
(C) The bowers of one species of bowerbird lack the towers and ornamentation characteristic of the bowers of most other species of bowerbird.
(D) Bowerbirds are found only in New Guinea and Australia, where local populations of the birds apparently seldom have contact with one another.
(E) It is well known that the song dialects of some songbirds are learned rather than transmitted genetically.
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