The three-spine stickleback is a small fish that lives both in oceans and in freshwater lakes. While ocean stickleback are covered with armor to protect them from their predators, lake stickleback have virtually no armor. Since armor limits the speed of a stickleback’s growth, this indicates that having a larger size is a better defense against the lake stickleback’s predators than having armor.

Summarize Argument: Phenomenon-Hypothesis
The author hypothesizes that a lake stickleback’s having a larger size is a better defense against its predators than having armor. This is based on the fact that ocean stickleback have armor for protection, whereas lake stickleback have almost no armor. In addition, armor limits the speed of a stickleback’s growth.

Notable Assumptions
The author assumes that lake stickleback are larger than ocean stickleback. In addition, the author assumes that the need to protect from its predators is the reason lake stickleback are larger and lack armor.

A
Sticklebacks with armor are unable to swim as fast, making them most vulnerable to fast-moving predators.
This is a disadvantage of having armor. This doesn’t undermine the author’s hypothesis, because it’s possible lake predators are fast-moving, making armor less effective against them.
B
Having a larger size is an important factor in whether lake stickleback, but not ocean stickleback, survive cold winters.
This raises a potential alternate explanation for the lake stickleback’s larger size. The author thinks the larger size must have something to do with protection from predators. But it might instead be due to the need for surviving cold winters.
C
Unlike ocean stickleback, the lake stickleback are more often preyed upon by predatory insects than by larger fish.
This doesn’t undermine the author’s hypothesis, unless you make the unwarranted assumption that a larger size wouldn’t be necessary or more effective at deterring insect predators. We have no reason to think a larger size is better defense than armor only against larger fish.
D
Both ocean stickleback and lake stickleback feed primarily on the same types of foods.
This concerns the diet of each stickleback. This has no clear relationship to lake sticklebacks’ larger size or lack of armor.
E
Sticklebacks originated in the ocean but began populating freshwater lakes and streams following the last ice age.
This relates to the origin of sticklebacks. This has no clear relationship to lake sticklebacks’ larger size or lack of armor.

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A company produced a small car that costs much less—but is also much less safe—than any car previously available. However, most customers of the new car increased their safety on the roads by buying it.

"Surprising" Phenomenon
A new car was much less safe than any other car previously available, yet most customers increased their safety after buying it.

Objective
The right answer will be a hypothesis that explains how a relatively unsafe car can increase driver safety. The explanation must show how two opposite qualities can coexist, likely through the intermediary—the driver. It may state that drivers are more likely to be careful on the roads knowing their vehicle is unsafe, or that all the customers owned even less-safe vehicles before.

A
The company surveyed potential customers and discovered that most of them were more concerned about cost than about safety.
We don’t care what people cared about when buying the car. We need to know why they were safer on the roads after buying it.
B
The company could significantly increase the car’s safety without dramatically increasing its production cost.
We’re not interested in what the company could do. We’re interested in the drivers.
C
Most people who bought the new car were probably unaware that it is much less safe than other cars.
If customers were unaware that the car was relatively unsafe, then we have no reason to believe they would’ve driven more carefully than before. This doesn’t resolve anything.
D
Many households that previously could afford only one car can now afford two.
Why would having two cars in their household make a driver safer? This doesn’t resolve the paradox—that driving a relatively unsafe car made these drivers safer.
E
Most people who bought the new car previously travelled by bicycle or motorcycle, which are less safe than the new car.
Even though the car in question is unsafe compared to other cars, it’s a big step up safety-wise from bicycles and motorcycles. Hence, customers who previously rode bicycles or motorcycles became safer on the roads once they bought the new car.

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An online auction site conducted a study of auction techniques involving 8,000 used cars, divided into two equal groups. Each car’s listing in the first group included a brief description of its condition. The description of each car in the other half additionally listed defects of the car. More cars in the second group sold, and of comparable cars in both groups that sold, the cars in the second group fetched higher prices.

"Surprising" Phenomenon
Cars sold more frequently and for higher prices when their defects were listed.

Objective
The correct answer will be a hypothesis that explains something about consumer behavior. The explanation must result in consumers responding more favorably to listings that report defects than to listings that only give brief descriptions. The explanation must also provide some rationale for why this is, which likely has to do with consumer trust.

A
Most people are skeptical of the descriptions that accompany items when they are put up for auction online.
We need a comparative aspect. This tells us people are skeptical of descriptions, but we don’t know how they respond to lists of defects.
B
People are likely to assume that a car with no reported defects has been maintained more attentively and is therefore in better overall condition.
If this were true, people would presumably prefer to buy the cars without reported defects. The stimulus tells us the opposite is true.
C
Prospective buyers are likely to overlook mention of defects buried in a detailed description of the condition of an object they are considering purchasing.
According to the stimulus, all the descriptions are brief. We don’t care about detailed descriptions.
D
Listing defects in a description of an item tends to lead people to assume that no major defect has gone unmentioned.
When defects are reported, people assume they’re getting the whole picture. When details aren’t reported, people may assume something about the car’s condition is being hidden, which makes them less inclined to make a purchase.
E
With thousands of cars for sale, prospective buyers are unlikely to read detailed descriptions of more than a small fraction of them.
Like (C), we don’t have detailed descriptions in the stimulus. We’re talking about brief descriptions and lists of defects.

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Critic: Linsey has been judged to be a bad songwriter simply because her lyrics typically are disjointed and subjective. This judgment is ill founded, however, since the writings of many modern novelists typically are disjointed and subjective, and yet these novelists are widely held to be good writers.

Summarize Argument: Counter-Position
The author concludes that the view that Linsey is a bad songwriter is ill founded. The view that the author criticizes is based on the fact that Linsey’s lyrics are usually disjointed and subjective. But the author points out that the writings of modern novelists are often disjointed and subjective, but these novelists are considered good writers.

Identify Conclusion
The conclusion is the author’s assessment of the view that Linsey is a bad songwriter: “This judgment is ill founded.”

A
Linsey is a good songwriter.
This goes too far. The author never suggests Linsey is good. He only asserts that the view that she’s bad lacks support.
B
The view that Linsey is a bad songwriter is poorly supported.
This is a paraphrase of the conclusion.
C
The writings of many modern novelists are disjointed and subjective.
This is a premise.
D
Many modern novelists are widely held to be good writers.
This is a premise.
E
Linsey’s talent as a writer is no less than that of many modern novelists.
The author never claims that Linsey is as talented as many modern novelists. He brings up modern novelists only to show that disjointed and subjective writings do not automatically make one a bad writer.

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