"Surprising" Phenomenon
Why were fewer bass caught after the power plant started discharging wastewater into the river?
Objective
The correct answer must fail to explain why fewer bass were caught downstream. Meanwhile, every wrong answer will state a difference between the periods before and after the power plant opened that implies bass were more scarce afterward, or that bass present were caught at a lower rate.
A
The discharged wastewater made the river more attractive to fish that are the natural predators of bass.
This would explain why fewer bass were caught after the power plant opened. Their predators became more prevalent, so the number of bass declined.
B
The discharged water was warmer than the normal river temperature, leading the bass to seek cooler water elsewhere.
This would explain why fewer bass were caught after the power plant opened. They fled for cooler water, decreasing their numbers in that part of the river.
C
Because of the new plant, access to the part of the river downstream from the plant was improved, leading to an increase in the number of anglers fishing for bass.
This does not explain the decrease because more anglers would cause more bass to be caught. This would contribute to an increase in the number of bass caught, not a decrease.
D
Because of the new plant, the level of noise downstream increased, making that section of the river a less popular place for anglers to fish.
This would explain why fewer bass were caught downstream. There may be no fewer bass, but the number of anglers fishing for them decreased, leading to fewer bass being caught overall.
E
The discharged wastewater created turbulence that disrupted the vegetation of the river downstream, destroying some of the bass’s natural habitat.
This would explain why fewer bass were caught downstream. Their habitat was destroyed, so bass perished or fled, leading to a decrease in their population.
"Surprising" Phenomenon
Why did amateurs win most of the prizes when the contest was open to professional photographers?
Objective
The correct answer will be an unsatisfactory hypothesis, because it will fail to explain why amateurs won most of the prizes. Every wrong answer, meanwhile, will identify a difference between amateur and professional entrants that implies amateur photographers had an advantage.
A
Many more of the entries in the contest were from amateurs than were from professionals.
This would explain why amateurs won a majority of the prizes. If more photographs were entered by amateurs, amateurs as a collective had more chances to win prizes than professionals did.
B
The judges in the contest were amateurs, and amateurs tend to prefer photographs taken by other amateurs.
This would explain the amateurs’ success. If the judges had a preference for amateur photographs, they would be more likely to award prizes to amateur entrants than to professional entrants.
C
Amateurs tend to enter their best photographs while professionals tend to save their best work for their clients.
This would explain why amateurs won more prizes than professionals. If amateurs submitted their best work and professionals did not, the quality of amateur photographs entered may have exceeded the quality of the professional photographs entered.
D
Each category in the contest was restricted to amateurs only or professionals only, and there were more categories open to amateurs.
This would explain why amateurs won a majority of the prizes. If most of the prizes were open only to amateurs, then amateurs were bound to win a majority of them.
E
Three times as many amateurs entered the contest as had entered in any previous year.
This provides no information about the number of amateur entrants relative to the number of professional entrants. It is still possible more professionals entered the contest than amateurs, in which case the outcome remains unexplained.
Summarize Argument
The author claims that “one’s being at home is not required for one’s being in one’s own house.” To back up this claim, we are offered an example: if you visit a house that you own but rent to someone else, you can be in your house but not at home (because it’s someone else’s home).
Identify Argument Part
The claim that one can be at home without being at one’s house doesn’t actually form part of the argument. Instead, it’s a piece of context that introduces the substance of the argument. Because the conclusion only focuses on being in one’s house without being at home, being at home without being at one’s house is ultimately irrelevant to the conclusion.
A
The claim is required to establish the conclusion.
The claim about being at home without being in your house doesn’t actually support the conclusion at all, because the conclusion is just about being in your house without being at home. That means it can’t be essential for the conclusion.
B
The claim represents the point the conclusion is intended to refute.
The author never states a point that the conclusion is meant to refute; the argument isn’t aimed against anything.
C
The claim is compatible with the truth or falsity of the conclusion.
This accurately describes the claim about being at home without being in your house. True or false, it doesn’t affect the conclusion, which is just about being in your house without being at home. If you removed this claim from the stimulus, it wouldn’t change anything.
D
The claim points out an ambiguity in the phrase “at home.”
The author never claims that the phrase “at home” is ambiguous. The argument is meant to establish an unexpected relationship between being at home and being in your house, which is possible because each of those concepts is clear.
E
The claim inadvertently contradicts the conclusion.
The claim about being at home without being in your house doesn’t contradict the conclusion at all. It’s entirely possible for both statements to be true; neither interferes with the other.
"Surprising" Phenomenon
Why are residents of Limone exempt from cardiovascular disease despite their high cholesterol levels?
Objective
A hypothesis explaining this condition must state a key difference between residents of Limone and other people with high cholesterol. That difference must protect Limone residents from cardiovascular disease, either because of a separate health factor or because Limone offers a small sample size.
A
Persons who come from families that have enjoyed great longevity tend not to develop cardiovascular disease.
This is not relevant because it is not stated whether families in Limone have enjoyed great longevity.
B
The stress and pollution found in large cities exacerbate existing cardiovascular disease, but there is little stress or pollution in Limone.
This would explain less severe cardiovascular disease in Limone, but not its total absence. It does not state that cardiovascular disease is caused by stress or pollution, only that those factors exacerbate it.
C
The residents of Limone have normal blood sugar levels, and very low blood sugar levels tend to cancel out the cardiovascular effects of a high cholesterol level.
This cardiovascular impact does not apply to Limone residents, so it cannot explain the absence of cardiovascular disease. Limone residents have normal blood sugar levels, but the effect described occurs only among people with very low blood sugar levels.
D
The residents of Limone inherited from common ancestors a blood protein that prevents vascular blockage, which is a cause of cardiovascular disease.
This difference between Limone residents and people in general can explain the absence of cardiovascular disease in Limone. Since Limone residents have a gene that prevents vascular blockage, they do not suffer from cardiovascular disease.
E
Olive oil is a staple of the diet in some parts of Italy, but unlike butter, olive oil is a monosaturated fat, and monosaturated fats do not contribute to cardiovascular disease.
This does not state that residents in these areas avoid fats like those in butter. It is possible they get similar fats from a different source, or that they consume high amounts of both butter and olive oil.