Summarize Argument
The author concludes that a newborn’s health largely depends on the amount of food available to the mother during pregnancy. He supports this by pointing out that records from 1850 to 1900 show that birth weights in a certain region were higher in years following successful crop harvests.
Describe Method of Reasoning
The author presents two sets of phenomena: birth weights and crop success, and newborns' health and food availability during pregnancy. He shows a correlation between the first two—higher birth weights in a certain region in years after successful crop harvests—and uses this to draw a conclusion about the second two, arguing that a newborn's health largely depends on the amount of food available to the mother during pregnancy.
A
inferring from a claimed correlation between two phenomena that two other phenomena are causally connected to one another
The author presents a correlation between two phenomena: birth weight and crop success in a region from 1850 to 1900. He then uses this to infer a causal connection between two other phenomena: a newborn’s health and the amount of food available to the mother during pregnancy.
B
inferring from the claim that two phenomena have fluctuated together that one of those phenomena must be the sole cause of the other
The author doesn't make this argument. Instead, he infers that because one set of phenomena fluctuated together, another set of phenomena is causally linked.
C
inferring from records concerning a past correlation between two phenomena that that correlation still exists
The author does present records from 1850 to 1900 concerning a correlation between two phenomena— birth weights and crop success. However, he uses this to infer a causal link between a different set of phenomena, not a current correlation between the same set.
D
inferring from records concerning two phenomena the existence of a common cause of the phenomena and then presenting a hypothesis about that common cause
The author doesn't discuss a common cause of the two sets of phenomena, nor does he present a hypothesis about a common cause. Instead, he uses a correlation between one set to draw a conclusion about the second set.
E
inferring the existence of one causal connection from that of another and then providing an explanation for the existence of the two causal connections
The author does infer the existence of a causal connection— that a newborn's health largely depends on the amount of food available to the mother during pregnancy— but he doesn’t infer it from another causal connection, nor does he provide an explanation for the connections.
Yolanda: Just as optometry relies on patients’ reports of what they see, happiness research relies on subjects’ reports of how they feel. Surely optometry is a scientific discipline.
Speaker 1 Summary
Vincent argues that scientific disciplines can only study things that can be measured. Because happiness is a subjective experience, it cannot be measured.
Speaker 2 Summary
Yolanda counters by making an analogy to optometry. She argues that optometrists rely on patients’ subjective reports of what they see, and that optometry is surely a scientific discipline.
Objective
Disagree: Vincent and Yolanda disagree over whether a scientific discipline can rely on subjective reports.
A
Happiness is an entirely subjective experience.
Vincent directly agrees with this in his argument, but Yolanda does not address whether happiness is an entirely subjective feeling. If anything, she may agree with this.
B
Optometry is a scientific discipline.
Yolanda agrees with this statement in her argument, but Vincent does not address anything about optometry. His argument is solely concerned with happiness.
C
A scientific discipline can rely on subjective reports.
Vincent opposes this statement in the first sentence of his argument. Yolanda agrees with this statement because she believes optometry is a scientific discipline despite relying on subjective reports.
D
Happiness research is as much a scientific discipline as optometry is.
Vincent has no position on this because he does not mention optometry. Yolanda also does not say anything that could support this comparative statement. She does not mention happiness or compare it to optometry.
E
Experiences that cannot be measured are entirely subjective experiences.
Neither Vincent nor Yolanda addresses whether unmeasurable experiences are subjective. Their disagreement centers around whether a scientific discipline can rely on subjective experiences.
Summarize Argument
The author’s main conclusion is that increasing urbanization might reduce the total amount of pollution in the nation. This is because people in more urban areas tend to rely more on mass transit and live in more energy-efficient houses than people in more rural areas. The same number of people in an urban area will produce less pollution than the same number of people in a rural area.
Identify Argument Part
The referenced text is the conclusion of the argument.
A
It is used to support the conclusion that people should live in large cities.
The referenced text is not a conclusion. Also, the author never suggests people should live in large cities.
B
It is a statement offered to call into question the claim that large cities are generally more polluted than the countryside.
The author concedes that large cities are generally more polluted than the countryside. This is not called into question by the author.
C
It is a statement serving merely to introduce the topic to be addressed in the argument and plays no logical role.
The referenced text is the conclusion.
D
It is a premise offered in support of the conclusion that large cities are generally more polluted than the countryside.
The referenced text is the conclusion. The claim that large cities are more polluted than the countryside is a concession.
E
It is a claim that the rest of the argument is designed to establish.
This accurately describes the role of the referenced text. It’s a conclusion supported by the claim that a given number of people will produce less pollution if concentrated in a large city than if dispersed among many small towns.
Summarize Argument
The author concludes that the mountain snowpack in the Rocky Mountains will probably melt more rapidly and earlier in the season, which will lead to greater spring flooding and less storable ater to meet summer demands. This is based on the fact that winter temperatures are likely to increase in the Rocky Mountains, and this will lead to a greater proportion of precipitation to fall as rain instead of snow.
Notable Assumptions
The author assumes that when a greater proportion of precipitation falls as rain instead of snow, that will cause the mountain snowpack to melt faster and earlier in the season. The author also assumes that faster and earlier melting of a snowpack will lead to more spring flooding and less storable water.
A
Global warming will probably cause a substantial increase in the average amount of annual precipitation in the Rocky Mountains over the coming century.
This tells us the overall amount of precipitation will increase. But that has nothing to do with the relative proportion of rain vs. snow, which we already know about. The premise isn’t about amount, it’s about proportion of rain vs. snow.
B
In other mountainous regions after relatively mild winters, the melting of snowpacks has led to greater spring flooding and less storable water, on average, than in those mountainous regions after colder winters.
This give us examples of what the author predicts in the conclusion. The fact (B) is about other mountainous regions doesn’t make it irrelevant. It’s still evidence that after a warmer winter, snowpacks will melt faster/earlier, leading to more flooding and less storable water.
C
On average, in areas of the Rocky Mountains in which winters are relatively mild, there is less storable water to meet summer demands than there is in areas of the Rocky Mountains that experience colder winters.
This doesn’t help establish that mountain snowpacks will melt faster and earlier. It also doesn’t involve the same region after a warmer than usual winter. Contrast that with (B), which does involve a comparison within the same region after a warmer winter.
D
On average, in the regions of the world with the mildest winters, there is more spring flooding and less storable water than in regions of the world with much colder winters.
This concerns regions of the world with the “mildest” winters. But we’re interested in what happens to a region when it has a milder than normal winter. This isn’t necessarily the “mildest.” (D) also doesn’t help establish snowpacks will melt faster and earlier.
E
The larger a mountain snowpack is, the greater the amount of spring flooding it is likely to be responsible for producing.
This creates a relationship between the size of a snowpack and the amount of flooding. But the premises don’t suggest the snowpack will be larger. The author predicts that the snowpack will melt faster and earlier because of the precipitation’s proportion of rain vs. snow.
Animal feed should not include genetically modified plants. A study found that laboratory rats fed genetically modified potatoes for 30 days tended to develop intestinal deformities and a weakened immune system, whereas rats fed a normal diet of foods that were not genetically modified did not develop these problems.
Summarize Argument
The author concludes that animal food should not contain genetically modified plants. He supports this by citing a study where rats fed genetically modified potatoes for 30 days developed intestinal issues and a weakened immune system, while rats fed a normal diet of non-genetically modified food did not have these problems.
Notable Assumptions
The author assumes that the study was representative and that the results observed in lab rats can be applied to all animals. Similarly, he assumes that the study on genetically modified potatoes can be generalized to all genetically modified plants, without considering differences between plant types.
He also assumes that the problems in the rats were caused solely by the genetic modification of the potatoes, without considering other factors or variables between the groups that could have influenced the results.
A
Potatoes are not normally a part of the diet of laboratory rats.
This highlights the assumption that the genetic modification of potatoes caused the rats' problems. But if potatoes aren’t typically part of lab rats’ diets and the other group ate a “normal diet,” it makes sense that the rats fed only potatoes might develop issues.
B
The rats tended to eat more of the genetically modified potatoes at the beginning of the 30 days than they did toward the end of the 30 days.
This doesn’t weaken the argument because, regardless of when in the 30 day study the rats ate most potatoes, they still developed intestinal deformities and weakened immune systems by the end of the study.
C
Intestinal deformities at birth are not uncommon among rats bred in laboratory conditions.
Even if this were true, the rats fed a normal diet would be expected to have intestinal deformities too. Also, the study focuses on problems that developed during the 30-day period, so any issues the rats had from birth wouldn’t affect the results.
D
Genetically modified potatoes have the same nutritional value to rats as do potatoes that are not genetically modified.
The nutritional value of genetically modified potatoes versus normal potatoes is irrelevant to this argument, which only addresses the effects of genetically modified potatoes.
E
The researchers conducting the study were unable to explain how the genetic modifications of the potatoes would have caused the intestinal deformities or a weakened immune system in the rats.
Whether the researches could explain why the genetic modifications caused the rats’ problems does not weaken the author’s conclusion that they did cause the problems and thus shouldn’t be present in animal feed.
Summary
Vitamins A and D can be toxic at high levels, meaning it can be dangerous to greatly exceed recommended daily intake. Some vitamin-fortified foods have 100 percent of the daily intake of both vitamins. Many people overestimate what counts as a serving of these foods. Many people will consume two to three times the manufacturer-defined serving size.
Strongly Supported Conclusions
Some people who eat vitamin-fortified food are exceeding the recommended daily intake of vitamins A and D by eating two to three times the serving size.
A
Few people who consume vitamin-fortified foods are aware of the recommended daily intake of vitamins A and D.
This is unsupported because we aren’t given any information about the mental state or knowledge of people consuming fortified foods. We don’t know how many are aware of the excessive levels of vitamin A and D.
B
Some people who consume vitamin-fortified foods exceed the recommended daily intake of vitamins A and D.
This is strongly supported because we are told that some people exceed more than one serving of these foods daily, and each serving can contain 100 percent of the recommended daily levels of vitamins A and D.
C
Some people mistakenly believe it is healthy to consume more than the recommended daily intake of vitamins A and D.
This is unsupported because we are not told anything about what people know or believe.
D
Most people who eat vitamin-fortified foods should not take any vitamin supplements.
This is unsupported because people who eat vitamin fortified foods may eat less than a serving per day, which would warrant supplements. It is also possible that people should take vitamin supplements for those vitamins not included in the vitamin-fortified foods.
E
Manufacturers are unaware that many people consume vitamin-fortified foods in amounts greater than the standard serving sizes.
This is unsupported because we are not told anything about the knowledge or awareness of manufacturers regarding how consumers eat their foods.