Answer: Option A. -> It makes a general observation to be exemplified.
:
A
The best answer is A. In the first paragraph, the author presents a general observation about contemporary business; the rest of the passage narrates a specific series of recent events concerning two companies in particular. The story of these companies serves as an example that illustrates the observation being made in the first paragraph of the passage.
Choices B and C can be eliminated because the author does not advance an argument.
Although the passage does advance an argument, the author does not anticipate that the conclusions being drawn will be disputed, so choice D is also incorrect.

Answer: Option D. -> Illustrating a business strategy by means of a case history
:
D
The best answer is D. In the first paragraph, the author outlines a business strategy, “developing integrated approaches for successful mass production and distribution.” The rest of the passage discusses the rivalry between Beta and VHS producers for control of the global VCR market, an illustration of the use of this strategy by VHS producers. The author briefly evaluates the two competing technologies and traces the impact of each on the market, but neither of these is the passage’s primary concern, so A and B are incorrect.
Choice C is incorrect because no events are reinterpreted in the passage.

Answer: Option D. -> The speed with which the anteaters located their prey is greater than what might be expected on the basis of chance alone.
:
D
The best answer is D. The last sentence in the passage implies that the researchers believed that the anteaters’ locating of their unseen prey was too prompt and too deliberate to be accidental.
Choice A is incorrect: researchers were unable to confirm that the anteaters’ favorite prey, termites, emitted electrical signals, and the observation of anteaters locating ants’ nesting chambers “suggests”,rather than proves conclusively, that anteaters use their electroreceptors to find prey.
Choice B is incorrect because here is no indication in the passage that researchers believed that the anteaters’ behavior was a typical. Choice C is incorrect because, according to passage, the researchers believed that the anteaters “were using their electroreceptorsto locate the nesting chambers”.

Answer: Option D. -> VHS prerecorded videotapes were more available than Beta-format tapes
:
D
The best answer is D. The passage states that the “perception among consumers that prerecorded tapes were more available in VHS format further expanded VHS’s share of the market”.
None of the information given in the passage suggests that consumers thought the VHS-format was technically better (A) or less expensive than Beta (B).
Nor does the passage indicate that consumers believed that VHS-format VCR’s were the first on the market (C).

Answer: Option C. -> They can be trained to recognize consistently the presence of a particular stimulus.
:
C
The best answer is C. The passage states that anteaters were “successfully trained” by researchers “to distinguish between two troughs of water,” only one of which had an electrical field.
Choices A, B, D can be eliminated because they present hypotheses about anteater behavior that were not tested in the experiment and are not discussed in the passage.

Answer: Option C. -> The alignment of an automobile manufacturer with a petroleum company to ensure the widespread availability of the fuel required by a new type of engine developed by the manufacturer.
:
C
The best answer is C. The alliances formed by VHS producers with videotape manufacturers created partnerships between companies whose products were mutually interdependent. Choice (C), an alignment with the producer of a complementary product that is necessary for the original product to function correctly, offers the closest analogy.
An alignment between manufacturers of competing products (A) is not analogous, nor is an alignment with a parts manufacturer (B).
Choice (D) describe alignments with companies that distribute and market the product and are similar to some of the strategic alliances formed by VHS producers, but not to their alignment with videotape producers.

Answer: Option B. -> Researchers are able to detect a weak electrical signal emanating from the nesting chamber of an ant colony.
:
B
The best answer is B. The researchers’ hypothesis is “that anteaters use electroreceptors to detect electrical signals given off by prey.” Evidence that electrical signals emanate from the nesting chamber of an ant colony-on which anteaters are known to prey-would strengthen the hypothesis.
Choice C may actually weaken the hypothesis: the passage implies that the rapidity with which anteaters were able to locate ants’ nesting chambers suggested to researchers that anteaters were using electroreceptors to locate prey.
Choice A and D provide evidence that does not strengthen the hypothesis.

Answer: Option D. -> The amount of electrical stimulation required to excite electroreceptors.
:
D
The best answer is D. According to the passage, the electrorecepors in the snouts of spiny anteaters responds to extremely weak electrical fields. The author of the passage contrasts these electroreceptors with tactile receptors, stating that it takes field strengths “about 1,000 times greater than those known to excite electroreceptors” to excite the tactile receptors on an anteater’s snout. The passage does not contrast the two types of receptors with regard to the characteristics mentioned in choices A, B and C.

Answer: Option D. -> Sharing control of the marketing of VHS-format VCR’s.
:
D
The best answer is D. VHS producers formed “strategic alliances with other producers and distributors” that helped manufacture and market their product, whereas Beta manufacturers “were reluctant to form such alliances and eventually lost ground”.
Choice A is incorrect because it describes the strategy used by Beta producers.
Choice B is incorrect because, although VHS producers held an early lead in sales, they did not give up their advantage.
Choice C is also incorrect: the passage states that VHS manufacturers took advantage of “strategic alignments with producers of prerecorded tapes”, but no mention is made of a strict VHS monopoly on such tapes.

Answer: Option D. -> test the hypothesis that meteor streams become broader as they age.
:
D
This question asks what the author says about the purpose of the research described in the first paragraph. The best answer is D. According to the author, the purpose of the computer-modeling experiment was to test the hypothesis that meteor streams broaden with time. Choice A is not correct; although the observational data described in the last paragraph allowed scientists to estimate the age of the Geminid stream, this data was analyzed to confirm a surprising prediction made by the computer model. This analysis was not part of the original experiment. Choice B is also incorrect. Although the experiment yielded a surprising prediction about a particular feature of meteor streams, the purpose of the experiment was to determine whether meteor streams broaden with time, not to identify the various structural features of meteor streams. Choice C is not correct because the experiment was undertaken to test a general hypothesis about meteor streams. It was not undertaken to explore the nature of any particular meteor stream, and the passagenever suggests that the actual meteor streams used in the computer model was “particularly interesting”.