Summary
Forest fragmentation happens when development cuts large forests into smaller pieces. Some animals, like white-footed mice, thrive and multiply in these conditions. These mice are the main carrier of the bacteria that cause Lyme disease, which is passed to humans by deer ticks that bite the mice. Lyme disease is a debilitating illness.
Strongly Supported Conclusions
Forest fragmentation can be beneficial for some animals.
Combatting forest fragmentation may decrease populations of white-footed mice.
Combatting forest fragmentation may lessen instances of Lyme disease among humans.
Combatting forest fragmentation can be beneficial for human health.
Combatting forest fragmentation may decrease populations of white-footed mice.
Combatting forest fragmentation may lessen instances of Lyme disease among humans.
Combatting forest fragmentation can be beneficial for human health.
A
White-footed mice are very rarely found in unfragmented forests.
This is unsupported. The stimulus only tells us that white-footed mice thrive in fragmented forests, but gives no information about their existence or wellbeing in unfragmented forests.
B
The population density for most species of small animals increases when a continuous area of forest becomes fragmented.
This is unsupported. The stimulus only speaks to the population density of white-footed mice in fragmented forests. It gives no information about the population-density of any other species of small animals.
C
Forest fragmentation reduces the number and variety of animal species that an area can support.
This is unsupported. The stimulus does not tell us about the effects of forest fragmentation on other animal species apart from white-footed mice or on the biodiversity of an area as a whole.
D
Efforts to stop the fragmentation of forests can have a beneficial effect on human health.
This is strongly supported. Stopping forest fragmentation can decrease the population density of white-footed mice, which carry the bacteria that cause Lyme disease. Thus, it can have a beneficial effect on human health by reducing the risk of Lyme disease.
E
Deer ticks reach their highest population densities in small forest patches.
This is unsupported. We are told that white-footed mice reach their highest population densities in small forest patches. The only thing we know about deer ticks is that they can transmit Lyme disease.
Summarize Argument
The author argues that adding bike lanes to roads will not make cyclists safer because more bike accidents tend to happen on roads with bike lanes than on those without.
Identify and Describe Flaw
This is a correlation-causation fallacy. The argument overlooks the likelihood that roads with bike lanes have more cyclists, which could naturally explain the higher number of accidents without indicating that the bike lanes fail to make cyclists safer. In fact, there could be far fewer cyclists using the roads without lanes precisely because those roads are less safe.
A
overlooks the possibility that injuries sustained by bicyclists in accidents on roads with bicycle lanes are as serious, on average, as those sustained by bicyclists in accidents on roads without such lanes
This possibility is not a problem for the conclusion. Injuries being just as serious when bike lanes are present would provide yet another reason to believe that the lanes won’t improve safety.
B
fails to address the possibility that there are more bicyclists riding on roads with bicycle lanes than there are riding on roads without such lanes
This describes how the argument fails to consider that more accidents may be occurring on roads with bike lanes simply because there are more cyclists on those roads.
C
takes for granted that any road alteration that enhances the safety of bicyclists also enhances the safety of motorists
The argument never mentions motorist safety; the conclusion is about the safety of cyclists.
D
concludes that adding bicycle lanes to roads will fail to enhance the safety of bicyclists on the grounds that only some roads that currently have such lanes are safe
The argument cites a correlation between bike lanes and accidents as support; it doesn’t say that only some roads with lanes are safe.
E
takes statistical evidence that fails to support a conclusion concerning the safety of bicyclists as evidence that proves the opposite conclusion
The argument never opposes any other conclusion; it just assumes that a correlation between roads with lanes and accidents indicates that the lanes don’t enhance safety.
Cookie Cutters
64.1.13
57.3.18
55.3.09
39.2.05
25.4.24
Summary
Over the last few decades, public outcries against pollution caused stricter emissions regulations.
These regulations caused greatly improved air quality in the cities that had the most polluted air 30 years ago.
These regulations caused greatly improved air quality in the cities that had the most polluted air 30 years ago.
Very Strongly Supported Conclusions
Public outcries contributed to greatly improved air quality in the cities that had the most polluted air 30 years ago.
A
In the city with the worst air pollution today, the air quality is better than it was 30 years ago.
Unsupported. We only know that the air quality is better in the cities that had the most polluted air 30 years ago. We don’t know anything about the city with the worst air pollution today.
B
No city has worse air pollution today than it did 30 years ago.
Unsupported. We only know that the air quality is better in the cities that had the most polluted air 30 years ago. There might be some other cities in which air quality has gotten worse.
C
Most of the public outcries against pollution came from people in the cities that had the most polluted air.
Unsupported. The cities that had the most polluted air greatly improved, but this doesn’t necessarily mean that most of the public outcries came from people in those cities.
D
The most polluted cities today are not the cities that were the most polluted 30 years ago.
Unsupported. The air quality is better in the cities that were the most polluted 30 years ago, but these cities could still be the most polluted cities today.
E
Public criticism led to an improvement in the air quality of the cities that had the most polluted air 30 years ago.
Very strongly supported. Public criticism led to stricter emissions regulations, and those regulations led to improved air quality in cities that had the most polluted air 30 years ago. So, public criticism led to this improvement.
Summarize Argument: Counter-Position
The editorialist claims that unauthorized music-sharing services are not responsible for depriving musicians of their deserved earnings because other parties also take a cut of the musicians’ earnings.
Identify and Describe Flaw
The argument is flawed because it only shows that other parties (record companies, publishers, managers, etc.) are also responsible for taking money from musicians, but never actually absolves unauthorized sharing services of blame. It’s still entirely possible that these sharing services, like the other parties mentioned, are robbing musicians.
A
concludes that one party is not blameworthy merely because another party is blameworthy
This describes how the argument fails to prove that sharing services are not responsible for taking musicians’ earnings, but instead only provides evidence that others are responsible as well.
B
attempts to promote a particular behavior simply by showing that many people engage in that behavior
The argument does not attempt to promote any behavior; it only claims that these sharing services are not responsible for taking musicians’ earnings.
C
attacks a position based solely on the character of the people who hold that position
The argument never makes a personal attack on the character of the professional musicians in question. It mistakenly points to other guilty parties in an attempt to absolve music-sharing services of responsibility.
D
tries to show that a position is false simply by pointing out an undesirable consequence of holding that position
The argument does not point to any consequence of believing that music-sharing services rob musicians of royalties; it only claims that those services are not to blame.
E
treats a necessary condition for blameworthiness as though it were a sufficient condition for blameworthiness
The argument does not establish any requirement for being blameworthy. Further, the argument claims that what these services do is not sufficient to consider them blameworthy.
Social critic: The whole debate over the legal right of rock singers to utter violent lyrics misses the point. Legally, there is very little that may not be said. But not everything that may legally be said, ought to be said. Granted, violence predates the rise in popularity of such music. Yet words also have the power to change the way we see and the way we act.
Summary
The debate over the legal right of rock singers to say violent lyrics misses the point. There is legally very little that cannot be said. Not everything that can legally be said ought to be said. Violence came before the popularity of violent lyrics in music. Words can change how we see and how we act.
Strongly Supported Conclusions
There could be a relationship between violent song lyrics and violent views and actions.
A
If rock music that contains violent lyrics is morally wrong, then it should be illegal.
This is anti-supported because the author states that very little speech is illegal and that there is a difference between things that are legal and things that ought to be said. The author doesn’t advocate making any speech illegal.
B
The law should be changed so that the government is mandated to censor rock music that contains violent lyrics.
This is unsupported because the author does not advocate for a change in laws, and the author draws a distinction between what can be said legally versus what ought to be said.
C
Violent rock song lyrics do not incite violence, they merely reflect the violence in society.
This is anti-supported because the author states that words can influence how we act, meaning the author thinks it is possible for violent lyrics to lead to some violent acts.
D
If rock musicians voluntarily censor their violent lyrics, this may help to reduce violence in society.
This is strongly supported because the author states that words, exemplified by violent lyrics, can affect how people act. This means that choosing not to speak violent lyrics could reduce violent acts.
E
Stopping the production of rock music that contains violent lyrics would eliminate much of the violence within society.
This is unsupported because the author concedes that violent acts predate violent lyrics. While the author thinks there is a connection between words and actions, it is unclear that stopping these lyrics would eliminate “much” violence.
Summarize Argument: Phenomenon-Hypothesis
The official hypothesizes the new pesticide better protects some fruit against insect pests than the old pesticide, at least in the short term. Why? Because when the new pesticide was applied to a sample of pear trees over three years, those trees lost fewer pears to insects than they had over the previous three years.
Notable Assumptions
The official assumes there’s no other reason, besides the new pesticide, why insects ate a smaller proportion of the sample pears during the last three years than they ate during the previous three years.
A
peach trees grown in the district that were treated with the new pesticide instead of the old pesticide
This would neither strengthen nor weaken the official’s argument. He restricts his conclusion to “certain” fruits, so it would not affect his argument if peaches did worse than pears.
B
peach trees grown in the district that were treated with the new pesticide in addition to the old pesticide
This would neither strengthen nor weaken the official’s argument. He makes no claim about the effectiveness of the new pesticide when used in tandem with the old pesticide.
C
pear trees grown in the district that were treated with the old pesticide instead of the new pesticide
This strengthens the official’s argument. It implies pear trees treated with the new pesticide showed more resistance to insects than those treated with the old pesticide during the same time.
D
pear trees grown in a neighboring district that were treated with neither the old nor the new pesticide
This is irrelevant to the official’s argument. He makes no claim about the ability of untreated trees to keep their fruits safe from insects.
E
pear trees grown in a neighboring district that were treated with the new pesticide instead of the old pesticide
This slightly weakens the official’s argument—it doesn’t strengthen it. It suggests factors specific to District 10 could have been responsible for fewer pears being eaten by insects.