Summary
The more individual members of a species we study, the better we understand that species. The better we understand the behavior and ecological niche of an endangered species, the better our chance is of saving that species.
Strongly Supported Conclusions
Therefore, as a species becomes more endangered, the more difficult it is to acquire the understanding to save that species.
A
many endangered species will become extinct before we have the knowledge that is necessary to save them
We don’t know whether many endangered species will in fact become extinct. We only know that our chance of saving an endangered species increases if we better understand that species.
B
continued reduction of wildlife habitat will make the preservation of many endangered species impossible
We don’t know whether it’s impossible to save some endangered species if their habitats continue to be reduced. The stimulus does not address the reduction of wildlife habitats.
C
knowledge that contributes to saving endangered species becomes harder to get as species become more endangered
If the number of individual members of a species causally contributes to our understanding of that species, which in turn causally contributes to our chance of saving that species, it must be that the fewer the individuals left to study, the less our chance is of saving that species.
D
to save endangered species it is more important to acquire the right kind of knowledge than to take action
We don’t know whether acquiring knowledge is more important than taking action in order to save an endangered species. We only know that our chances of saving an endangered species increases as our understanding of that species increases.
E
the impact of human study of endangered species is sometimes more harmful than beneficial
We don’t know whether human study of endangered species is sometimes harmful.
Summary
The clock evolved from more complex to more simple. The earliest clocks were the most complicated, because they were used mainly for predicting astronomical phenomena. As timekeeping functions became more important, and astronomical functions less important, clocks became more simple.
Strongly Supported Conclusions
The level of clock complexity required for astronomical predictions is higher than that required for keeping time.
A
Present-day clocks are of no use in the prediction of astronomical phenomena.
Unsupported, because these clocks might have some use for astronomical predictions. We know that their primary purpose isn’t astronomical, but they might still be usable for some astronomical purposes.
B
The mechanisms used to predict astronomical phenomena in at least some clocks were more complicated than most more recent mechanisms used for this function.
Unsupported. We don’t know about mechanisms for predicting astronomical stuff outside of clocks. Non-clock mechanisms might be far more complicated than the mechanisms in clocks.
C
Clocks used only for keeping time do not differ appreciably in their mechanical complexity.
Unsupported, because there can still be differences in complexity among time-keeping clocks. On average, this category of clocks isn’t as complex as the clocks used to predict astronomical phenomena, but that doesn’t mean they all have the same complexity.
D
The mechanisms that the earliest clocks used to predict astronomical phenomena were more complicated than the mechanisms used for timekeeping functions in some more recent clocks.
Strongly supported, because we know that the earliest clocks were the most complex, because they were primarily used for astronomical predictions. More recent clocks are mainly used for time-keeping, which allows for less complex mechanisms.
E
Interest in predicting astronomical phenomena has declined steadily since the invention of the first mechanical clocks.
Unsupported, because people may simply be using other devices to satisfy their interest in astronomical predictions. Clocks are being used less for this purpose, but that doesn’t imply that overall interest in astronomical predictions is lower.
Summary
Most people’s bodies make enzyme CYP2A6, which plays a crucial role in eliminating nicotine from the body. Nicotine is the addictive drug in cigarettes. Smokers whose bodies make the most common form of this enzyme tend to smoke more than smokers whose bodies make some other form of the enzyme. Why? Because the faster nicotine is eliminated from the body, the faster a person will crave another cigarette.
Strongly Supported Conclusions
The most common form of the enzyme CYP2A6 is also the form that eliminates nicotine from the body the fastest.
A
the most common form of CYP2A6 is the one that most rapidly eliminates nicotine from the body
This answer is strongly supported. Since smokers with the most common form of the enzyme smoke more due to nicotine being eliminated from the body faster, the most common form of the enzyme must cause the rapid elimination of nicotine.
B
most people whose bodies make the rarest form of CYP2A6 do not smoke at all
This answer is unsupported. We don’t know what happens in people with the rarest form of CYP2A6.
C
if one’s body does not make CYP2A6, nicotine will still be eliminated, although very slowly
This answer is unsupported. We don’t know what occurs in people whose bodies do not produce the CYP2A6 enzyme.
D
the greater the quantity of CYP2A6 that one’s body makes, the faster nicotine will be eliminated
This answer is unsupported. We don’t know if there’s a proportional relationship between the quantity of the enzyme and nicotine being eliminated from the body.
E
helping to eliminate nicotine is not the only function that CYP2A6 serves
This answer is unsupported. We don’t know if there are any other functions the enzyme serves.
Santiago: I’m uncomfortable with the idea of calculating the biosphere’s dollar value in order to justify protecting it. Such an approach implies that the biosphere’s most important value lies in the “services” it provides us.
Speaker 1 Summary
Ellen says that we should prioritize protecting Earth’s biosphere. This is supported by a recent estimate by a group of experts that the biosphere provides $33 trillion worth of “services” to humans each year.
Speaker 2 Summary
Santiago concludes that we should not use an economic approach to justify protecting the biosphere. Why not? Because taking that approach implies that the biosphere is primarily important due to the “services” it provides. Santiago presumably thinks that the biosphere’s truest value lies elsewhere.
Objective
We want to find a disagreement between Ellen and Santiago. They disagree about whether economic valuation is a good justification for protecting Earth’s biosphere.
A
Estimating the dollar value of the biosphere’s essential services is an appropriate way of providing a rationale for making protection of the biosphere a high priority.
Ellen agrees and Santiago disagrees, so this is the disagreement. Ellen’s argument does exactly this, using an estimated dollar value to rationalize protecting the biosphere. Santiago, though, says that economic value is not how we should justify protecting the biosphere.
B
The biosphere’s most important value lies in something other than the services it provides to human beings.
Santiago agrees with this, but Ellen never disagrees. Ellen focuses on the value of the “services” provided by the biosphere, but doesn’t eliminate the possibility of a more important value.
C
Calculating the dollar value of the biosphere’s essential services is the most effective way to ensure that protecting the biosphere is treated as a matter of urgency.
Neither speaker talks about what would be the most effective way to ensure that the biosphere is urgently protected, so we can’t say that either Ellen or Santiago expresses an opinion.
D
The idea that the dollar value of the biosphere’s essential services can be accurately calculated is unrealistic.
Neither speaker makes this claim. Ellen accepts the idea of estimating this dollar value, and even Santiago doesn’t take issue with whether the calculation is realistic.
E
Calculating the dollar value of the biosphere’s essential services implies that the biosphere’s most important value lies in the services it provides to human beings.
Santiago agrees with this, but Ellen doesn’t disagree. Ellen doesn’t talk at all about the implications of doing this calculation, or about what the biosphere’s most important value is.
Summarize Argument
The analyst concludes Johnson’s campaign doesn’t actually believe his opponent’s quote was more damaging in context. Why not? Because they’ve passed on several more opportunities to quote her statement in context.
Notable Assumptions
The analyst assumes Johnson’s campaign continues to take the quote out of context because it believes the quote would be no more damaging in context. This means assuming there’s no other reason the campaign would continue to give the quote without context—such as convenience, for example.
A
In criticizing an opponent, political campaigns will pursue the line of attack they believe to be most politically damaging.
This makes concrete the analyst’s assumption that the campaign would only continue to use the quote out of context if it were at least as damaging as the quote in context. It rules out the possibility that considerations other than political damage are more important.
B
In criticizing an opponent, political campaigns do not use techniques that they would find objectionable if used against their candidate.
This principle doesn’t apply. There’s no indication Johnson’s campaign would find it objectionable if his opponent quoted him in context.
C
In criticizing an opponent, political campaigns are expected by voters to make sure that the quotes to which these campaigns refer are not taken out of context.
This principle doesn’t affect the argument. It implies the campaign must have some motivation for taking the quote out of context—but doesn’t make the particular motivation suggested by the analyst any more likely.
D
In criticizing an opponent, political campaigns will not be strongly criticized as long as the words attributed to their opponent were actually said by their opponent.
This doesn’t affect the argument. It implies Johnson’s campaign won’t be criticized either way—it doesn’t make it any more likely the campaign is lying.
E
In criticizing an opponent, political campaigns will avoid using techniques that leave their candidate open to effective counterattacks.
This principle doesn’t apply. There’s no indication that quoting Johnson’s opponent in context—as opposed to out of context—would make Johnson vulnerable to counterattack.
Sabine: That’s simply not true. The fact is, your barber makes money by convincing people to buy that product.
Summarize Argument: Counter-Position
Sabine argues that the barber’s claim is not true because the barber makes money by convincing people to buy the product.
Identify and Describe Flaw
This is the cookie-cutter “ad hominem” flaw, where the author attacks the source of the argument rather than the argument itself.
Here, Sabine dismisses the barber’s claim simply because the barber benefits from selling the product. Sabine never actually engages with the barber’s evidence, nor does she give any reason to believe that the product does not help prevent baldness.
A
discounts scientifically plausible evidence merely because the person offering it is not a scientist
Sabine doesn't address the fact that the barber is not a scientist. Instead, she discounts the barber’s claim merely because the barber benefits from selling the product.
B
takes for granted that a product will be harmful if it is sold on the basis of an unsubstantiated claim
Sabine never claims or assumes that the product will be harmful. She just says that it’s not true that the product helps prevent baldness.
C
rejects an explanation without proposing an alternative explanation
The barber explains that the product prevents baldness by blocking a certain chemical compound. Sabine rejects the claim that it prevents baldness, but she doesn’t challenge the barber’s explanation. She also doesn’t need to propose an alternative explanation.
D
draws a conclusion about someone’s motives for making a particular claim without providing evidence that any such claim was actually made
Sabine draws a conclusion about the barber’s claim based on an assumption about the barber’s motives. Her conclusion isn’t about the barber’s motives. Also, she doesn’t need to provide evidence that the barber’s claim was made; Kevin just said that it was made.
E
rejects a claim merely because the person making the claim stands to benefit by doing so
Sabine rejects the barber’s claim that the product helps prevent baldness merely because the barber stands to benefit from that claim. Sabine doesn't give any real evidence against the barber’s claim.
Summary
A theory surrounding the importance of vitamin C contends that it plays a crucial role in producing the body’s supply of collagen, a protein that is almost exclusively present in connective tissue and bone. Because of this, some doctors believe that vitamin C can be useful for treating symptoms of some common illnesses.
Strongly Supported Conclusions
Some common illnesses (or their symptoms) are caused by a lack of collagen in the body.
Some common illnesses impact the health of one’s connective tissue and bones.
Some common illnesses impact the health of one’s connective tissue and bones.
A
Some doctors believe that there are illnesses that affect the state of connective tissue or bones.
The stimulus says, “for this reason” (vitamin C plays a crucial role in producing collagen) some doctors think it can be useful to treat symptoms. It is reasonable to assume that these illnesses impact connective tissue and bone, where collagen is almost exclusively present.
B
Some doctors believe that vitamin C is the only substance that produces and maintains collagen.
There is no support to suggest that vitamin C exclusively produces collagen. The stimulus only specifies that collagen *almost* exclusively occurs in the body’s connective tissue and bones. But there is no link to vitamin C being the sole provider of it.
C
Some doctors believe that strengthening connective tissue and bones increases the body’s ability to use certain vitamins.
This has the logic flipped. It's reasonable to assume that some doctors believe vitamin C strengthens bones and connective tissue (not the other way around).
D
Some doctors believe that use of vitamin C is the most effective treatment for certain common illnesses.
This is too strong to support. The stimulus specifies that some doctors recommend vitamin C to treat some illnesses. But there is no evidence that it is the *most* effective treatment.
E
Some doctors believe that any illness that can be ameliorated with vitamin C causes deterioration of connective tissue and bones.
This is too strong to support and not very well supported. The stimulus only says that *some* (not any) illnesses can be helped by vitamin C. It is also a bit of an assumption to suggest that these illnesses cause deterioration in the bone.
Summarize Argument
You should only buy domestic seafood if you want to increase the chances that you’re buying seafood that is safe to eat. This is because only 2% of imported seafood is insepected.
Notable Assumptions
The author assumes that more than 2% of domestic seafood is subjected to health safety inspections.
A
Do the health safety inspections detect all health risks present in the seafood that is inspected?
Irrelevant—the usefulness of the inspections is not what we’re evaluating.
B
What kinds of health risks can seafood pose?
Irrelevant—the nature of the health risks posed by seafood is not relevant to the argument, which is about the relative safety of domestic vs. international seafood.
C
What percentage of imported food other than seafood is subjected to health safety inspections?
Irrelevant—we are only concerned with seafood. Other foods are outside the scope of the argument.
D
What percentage of domestic food other than seafood is subjected to health safety inspections?
Irrelevant—we are only concerned with seafood. Other foods are outside the scope of the argument.
E
What percentage of domestic seafood is subjected to health safety inspections?
This is useful. The answer to this question will tell us if the author is right to assume that domestic seafood is more likely to be inspected than imported seafood.
Summary
Consumers should be provided with relevant information in situations where it is difficult to make informed decisions about products. Requiring food manufacturers to print nutrition information on packaging solved the problem of consumers having difficulty determining whether a food contained nutritious ingredients. Many consumers are interested in conserving energy. There is no way for consumers to determine how much energy was required to make a product.
Strongly Supported Conclusions
Manufacturers should be required to label products based on how much energy was required to produce it.
A
consumers who are informed of the amount of energy used to produce a product should choose energy efficient products
This is unsupported because the problem is that consumers have difficulty becoming informed about the amount of energy used to produce a product in the first place.
B
manufacturers should use less energy while producing products
This is unsupported because the problem described is that consumers don’t have enough information about the products, not necessarily that too much energy is being used.
C
providing consumers with information about the energy used to produce a product would reduce the impact of fossil fuels on our lives and economy
This is unsupported because we don’t know how consumers would respond if the energy inputs were printed on products.
D
consumers should demand products that require less energy to produce
This is unsupported because the problem the author is trying to solve is consumers not having information on how much energy it took to make products. Demanding that products require less energy to produce doesn’t solve this information gap.
E
manufacturers should be required to label their products with information about the amount of energy used to produce those products
This is strongly supported because we get an analogous situation where printing nutrition information solved a consumer difficulty. Printing the energy used to produce products would solve a consumer difficulty as well.