PrepTest 111, Section 4, Question 23
The higher the altitude, the thinner the air.(23 more words not shown)
Which one of the following(11 more words not shown)
- AAs one gets(18 more words not shown)
- BThe more egg(33 more words not shown)
- CThe people who(38 more words not shown)
- DThe older a(36 more words not shown)
- EThe bigger the(26 more words not shown)
Reading the argument
Could weather or some other condition affect the air too? Perhaps, but this argument gives us a simple rule to work with: the higher the altitude, the thinner the air. It then compares two cities and applies that rule.
What we’re looking for
For a parallel argument, I want to keep the relationship straight. Mexico City has more of the first thing—altitude—so it must have more of the second—air thinness. A matching answer should give us a comparable rule, establish a difference between two things, and draw the corresponding comparison. Similar subject matter won't be enough; the rule has to support the comparison the answer actually makes.
Working the answers
- A
This looks promising at first: Henrietta is older, so she must be wiser. But read the rule carefully. “As one gets older one gets wiser” describes a person's change over time. It doesn't say that every older person is wiser than every younger person.
Imagine using made-up wisdom scores just to see the problem. Henrietta could move from 1 to 2 as she ages, while her daughter moves from 5 to 7. Both get wiser, but the younger person remains wiser. A has switched from improvement within each person's life to a comparison between different people. The original altitude rule supports the comparison between the cities directly.
- B
The rule depends on two things: how many egg whites are used and how long they are beaten. We learn only that Lydia used more egg whites. What if Joseph beat his much longer? B leaves a relevant part of its own rule unresolved. The original argument doesn't introduce a second factor and then ignore it.
- C
This compares the fastest marathon runners in two different periods, then reaches a conclusion about Charles's own improvement. Charles might not be one of the fastest runners in either period. Better performances by the leading runners don't establish that this particular runner has improved. The rule and the conclusion concern different comparisons.
- DCorrect
Tree age plays the role of altitude, and number of rings plays the role of air thinness. The rule says an older tree has more rings. Lou's tree is older than Theresa's, so Lou's tree has more rings.
Each step lines up: a general relationship, two things compared on the first feature, and the corresponding conclusion about the second feature. Unlike A, this rule directly compares different trees, rather than merely saying that an individual changes over time.
- E
The rule starts with vocabulary size and leads to difficulty. But the evidence gives us difficulty, and the conclusion tries to work back to vocabulary size. English could be harder for some other reason, such as grammar. The original argument starts with the feature named first in its rule and follows it to the result; E starts with the result and assumes it identifies that one cause.
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