Reading comp PrepTest 132 · Section 1 · Question 20

Passage

Questions 15-21 Passage A  .        Because dental caries (decay) is strongly linked to  . consumption of the sticky, carbohydrate-rich Remaining source text redacted.
Passage walkthrough
Passage Summary

Topic: Science


Passage A

Paragraph 1

  • Paragraph note
    • Factors in decay; connection; what it can show
  • Views, minor Meta-Structures, points of intersection, and the author's attitude
    • Connection - Dental caries (decay) and sticky carbs
    • Show - When humans went from hunting to agriculture
    • Factors in decay (don’t try to memorize)

Paragraph 2

  • Paragraph note
    • Research and examples of connection
  • Views, minor Meta-Structures, points of intersection, and the author's attitude
    • Conclusion - Carbs are linked to caries
    • Leigh - Sioux (meat, no caries) and Zuni (carbs/agriculture, caries)
    • Others confirm

Paragraph 3

  • Paragraph note
    • Exceptions (examples)
  • Views, minor Meta-Structures, points of intersection, and the author's attitude
    • Exceptions - Nonagricultural groups who had caries - at more cariogenic carbs
    • Examples - Western North America (stone-ground acorns); Hopi (pinyon nuts and tubers)

Passage B

Paragraph 1

  • Paragraph note
    • Background
  • Views, minor Meta-Structures, points of intersection, and the author's attitude
    • Ban Chiang skeletons found - 2000 year period from hunter to agriculture

Paragraph 2

  • Paragraph note
    • A trend is noted and explained
  • Views, minor Meta-Structures, points of intersection, and the author's attitude
    • Trend - More agriculture = declining health (including caries)
    • Why? More sticky carbs
    • Why? Less tooth wear (fiber/grit) that removes fissures in carb diet
    • (Exception - Too much wear causes caries)

Paragraph 3

  • Paragraph note
    • Expectation in example from Paragraph 1
  • Views, minor Meta-Structures, points of intersection, and the author's attitude
    • Ban Chiang - Ate carbs throughout 2000 year period
    • Expectation - Carbs should have led to caries

Paragraph 4

  • Paragraph note
    • A paradox is introduced; potential resolutions noted
  • Views, minor Meta-Structures, points of intersection, and the author's attitude
    • Paradox - More frequent caries in early group despite increasing agriculture
    • Ruled out explanation - Changes in tooth wear (no changes seen)
    • Potential explanation - Diet remained varied and switched to less bad carbs

Main Points:

Passage A - While there are some exceptions, a shift to agriculture and consumption of “sticky” carbs increases the frequency of dental caries in a population.

Passage B - Remains found at Ban Chiang present a paradoxical case where increased reliance on agriculture resulted in fewer dental caries - contrary to expectations - which may be explained by their overall diet and switch from certain carbs to others.

Key Lines?

Passage A:

  • Lines 1-3 - A relationship is established
  • Lines 3-5 Using one thing as a proxy for another is discussed
  • Line 6 - A list of factors is introduced
  • Line 12 - A list of examples/research is started
  • Lines 23-25 - An exception is noted
  • Line 25 - More examples are started

Passage B:

  • Lines 39-41 - A relationship is established
  • Lines 42-44 - Two potential explanations are established
  • Line 57 - A paradox is previewed (“should theoretically”)
  • Lines 58-60 - The paradox is stated
  • Lines 61-62 - One explanation from earlier is ruled out
  • Lines 63-69 - Potential explanations are presented

Meta-Structure? Relationship Between Passages?

Generalization/Example (Passage A) - Passage A presents several generalizations that it follows up with examples. This happens in both Paragraphs 2 and 3.

Exception (Passage A) - After discussing a general rule throughout the first two paragraphs, the Author shifts to discussing a class of exceptions to that rule.

Overarching Example (Passage B) - Unlike Passage A, Passage B focuses on a single example - that of the skeletal remains found in Ban Chiang.

Paradox/Resolution (Passage B) - Passage B introduces a paradox (“Yet”). According to expectations, as the Ban Chiang population relied more on agriculture, they should have seen more caries. Evidence says that the frequency of caries went down. The passage then rules out one explanation before presenting alternatives as possibilities (“more likely that”).

The two passages both deal with the same topic - the relationship between an increased reliance on agriculture and the frequency of dental caries/tooth decay. And both are largely aligned in that they treat it as a general rule that more agriculture results in more tooth decay (Lines 11-12; Lines 39-41). And neither concludes that this is wrong - instead, they both present exceptions. In the case of Passage A, the Author explicitly mentions exceptions (Paragraph 3). In Passage B, the Author explores an exceptional case (Line 57; Lines 58-60) and presents potential reasons that this case doesn’t conform to the norm (varied diet; switch to less cariogenic carbs).

Last Thoughts?

These passages have a lot of overlap between them, so we should expect more questions about similarities than differences.

Question prompt

Each passage suggests which Remaining source text redacted.
Why the credited answer is right

Credited answer: C

The notes below walk through why it fits the stem and how to eliminate the rest.

Question Type

Social Science

Strategy Overview

Head straight to the answers, using our overall understanding of the passages to identify ones that seem likely, and then use our notes and the passages to find the correct answer

Answer Anticipation

This question is very similar to Question #19. Both passages spoke extensively about carbohydrate-rich foods - it was a central cause of dental caries in each - and both were largely aligned, so there’s quite a lot of things we could anticipate here as far as a correct answer goes. As such, we should head straight to the answers and use our overall understanding to identify ones that are in play, deferring on those that don’t line up with the passages. For the ones in play, we should then use our notes to find support in each passage and, when we do, we’ll have our correct answer.

Answer choices

  1. A
    Varieties that are cultivated Remaining source text redacted.
    Why choice A is not credited

    (A) (Lines 13-18; Lines 26-29; Lines 51-53) Passage A compares cultivated maize to meat, and it discusses the high caries rate of wild (“gathered”) acorns that have been processed, but it doesn’t compare cultivated to wild varieties of carb-heavy foods. Passage B discusses only cultivated rice and yams. This answer, thus, features an unsupported comparison.

  2. B
    Those that require substantial Remaining source text redacted.
    Why choice B is not credited

    (B) (Lines 26-29; Lines 34-36) Passage A brings up a nonagricultural society that at “highly processed” stone-ground acorn flour. Passage B mentions the early Ban Chiang population had a hunter-gatherer-cultivator economy, but it doesn’t go enough into their diet to know if they skipped over highly processed carbs. As such, neither passage supports this answer.

  3. C
    Some of them naturally Remaining source text redacted.
    Why choice C matches the stem

    (C) (Lines 25-31; Lines 66-69) Passage A mentions that highly processed stone-ground acorn flower resulted in high caries frequency, and several wild plants collected by the Hopi showed “high cariogenic potential,” suggesting that there’s variability to the cariogenic potential. Passage B notes that rice is a “less cariogenic carbohydrate” than yams. Both feature comparative language when discussing how cariogenic certain carbs are, supporting this answer.

  4. D
    Some of them reduce Remaining source text redacted.
    Why choice D is not credited

    (D) (Lines 44-50) While fiber does wear down teeth and prevent caries, Passage B doesn’t connect carb-rich foods to fiber - in fact, it notes as a shift is made to an agricultural diet (which is generally heavier in carbs - think of that delicious wheat) there’s less fiber in the diet. Passage A also doesn’t mention this at all.

  5. E
    The cariogenic potential of Remaining source text redacted.
    Why choice E is not credited

    (E) (Lines 16-18; Line 28; Line 29; Lines 51-53) Passage A talks about cultivated maize, but it never talks about wild maize. And it talks about gathered acorns and wild plants, but never cultivated versions of them. Passage B talks about cultivated yams and rice, but never wild yams and rice. This answer is unsupported in either passage.

What this tests

Question analytics

Based on historical answer selection rates for this question.

Answer choice distribution

  1. A 13%
  2. B 5%
  3. C Credited 68%
  4. D 6%
  5. E 8%

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