Reading comp PrepTest 150 · Section 1 · Question 3

Passage

Questions 1-5  . The following passage was written in the mid-1990s.  .             Evidence that the earth's atmosphere has warmed  . Remaining source text redacted.
Passage walkthrough
Passage Summary

Topic: Science


Paragraph 1

  • Paragraph note
    • Phenomenon: Earth's annual temperature increase; evidence links the increase to the greenhouse effect
  • Views, minor Meta-Structures, and the author's attitude
    • Comparison:
      • The current average temperature is about 0.5 degrees Celsius higher than it was 100 years ago (second sentence)
    • Cause-and-effect relationship, according to proponents of the greenhouse effect:
      • Elevated levels of certain gases cause heat to be trapped in the earth's atmosphere (last sentence)
    • Author's attitude: "quite compelling" (first sentence); "unprecedented" (second sentence); "strengthened" (last sentence); "controversial" (last sentence)

Paragraph 2

  • Paragraph note
    • Inconsistencies in greenhouse effect data and correction with updated data taking sulfates into account
  • Views, minor Meta-Structures, and the author's attitude
    • Comparison, according to early models of the greenhouse effect:
      • Models estimate that increase in the earth's atmosphere should have been higher than the observed increase (first sentence)
      • Taking into account sulfates causes data to be consistent with observed temperatures (last sentence)
    • Cause-and-effect relationship:
      • Airborne sulfates cause solar energy to reflect back to space, which causes a lowering of the temperature (third sentence)
    • Example of sources of sulfates:
      • Natural sources, like volcanoes (third sentence)
      • Human technological sources (third sentence)
    • Author's attitude: "somewhat inconsistent" (first sentence); "more accurately" (second sentence); "important factor" (second sentence)

Paragraph 3

  • Paragraph note
    • Alternative explanation (solar energy) and rebuttal (can't explain long-term and extreme fluctuations); author's conclusion
  • Views, minor Meta-Structures, and the author's attitude
    • Solar energy view:
      • The sun's heating effects have changed the earth's atmospheric temperature (first and second sentences)
    • Author's view:
      • Solar energy models can explain yearly fluctuations but not the long-term, extreme increases in average temperature (third through fifth sentences)
      • The earth's annual temperature has increased, and the greenhouse effect is the best explanation for that increase (last sentence)
    • Author's attitude: "strong" (second sentence); "cannot account for the entirety" (third sentence); "it seems reasonable to conclude" (last sentence)

Main Point: New methods in data collection and analysis establish the greenhouse effect as the most likely cause of the rise in annual global temperatures.

Key Lines?

Paragraph 1, Sentence 1 (P1, S1) - Description of phenomenon (rise in temperatures)

P1, S3 - Explanation of phenomenon (greenhouse effect)

P2, S1 - Issue with explanation (inconsistencies in early models)

P2, S2-4 - Correction of the issue (airborne sulfates account for inconsistencies)

P3, S1 - Alternative explanation (changes are due to variations in solar energy)

P3, S3 - Rebuttal of the alternative explanation (can't account for the entirety)

P3, S6 - Author's conclusion

Meta-Structure?

Phenomenon/Explanation: This passage follows the Phenomenon/Explanation Meta-Structure. When passages utilize this Meta-Structure, the initial paragraphs typically describe an observable fact, behavior, or situation. We call these "phenomena." The author then describes one or more "explanations" of why the observable fact, behavior, or situation occurs in later paragraphs.

This passage follows that model closely. In the first two sentences of the first paragraph, the author describes and supports the phenomenon — Earth's increasing annual temperatures — through references to data. In the last sentence of that paragraph, the author introduces a "controversial" explanation for the increase: the greenhouse gas effect. The author describes and accounts for some issues with this explanation in the second paragraph and rebuts an alternative explanation in the third paragraph*. Ultimately, the author concludes that the greenhouse effect is the best explanation for the phenomenon in the last sentence. Since the main point is generally the explanation the author presents or endorses in a Phenomenon/Explanation passage, we can use that sentence to help us answer the main point question.

*Because the author uses the second and third paragraphs to rebut criticisms or issues with the greenhouse effect explanation, some may view this as a Rebutting Critics or Criticizing a Viewpoint passage. However, these rebuttals support the author's preferred explanation, so we felt the Phenomenon/Explanation Meta-Structure fit this entire passage's structure better.

Last Thoughts?

Passages tend to be a bit dated in Reading Comprehension. So, if you felt it was odd that the passage referred to the link between atmospheric gases and temperature increases as "controversial" within the scientific community, that's your explanation. (Helpfully, the caption above the passage clarifies how old this passage is.) Let this remind us that we shouldn't bring our prior knowledge or assumptions about a topic into our reading method. While we may rely on some well-known or common-sense beliefs and suppositions in Reading Comprehension (for instance, it would be difficult to understand this passage without knowing that there's an atmosphere surrounding the earth), almost everything we'll need to answer the questions is written in the passage. We need to read and understand the actual text of the passage — we shouldn't rely on any specific or specialized extra-textual knowledge or beliefs about the subject matter on Reading Comprehension.

Question prompt

Which one of the Remaining source text redacted.
Why the credited answer is right

Credited answer: A

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

Question Type

Science

Strategy Overview

Remind ourselves of the main point of the passage, then head to the answers, focusing on those that line up with the main point and then using our notes/the passage to find the correct answer

Answer Anticipation

This question stem provides no indication as to the topic of the correct answer or where it'll show up in the passage. As such, we'll need to rely on our big-picture understanding of the passage to answer this question. We should start by reminding ourselves of the main point (either by reviewing what we said after reading the passage or by re-reading our answer to the main point question). From there, we can head to the answer choices. If something in an answer choice doesn't seem familiar, we shouldn't check the passage to see if it was mentioned. Instead, we'll table it and move on to the next answer choice. If something seems inconsistent with the main point, we can eliminate it. If something seems familiar and consistent with the main point, we'll use our notes/highlights/underlines to find the part of the passage that proves the answer choice must be true. If we can find that confirmation, we'll select that answer choice and move on.

Answer choices

  1. A
    the way in which Remaining source text redacted.
    Why choice A matches the stem

    (A) Do you remember reading about sulfates' effect on temperatures?

    Probably. Sulfates were the key to how the author resolved the discrepancy with the data, and we included them in our note for the second paragraph ("Inconsistencies in greenhouse effect data and correction with updated data taking sulfates into account"). So, this answer choice seems like a good bet.

    So, it makes sense to verify whether this answer choice is supported by the passage by checking the second paragraph. Upon review, we'll see that sulfates "counteract the heating effect of greenhouse gases by reflecting solar energy back into space" (P2, S3). So, sulfates' effect on temperatures is mentioned in this passage. Therefore, we can select this answer choice and move on to the next question without assessing the remaining answer choices.

  2. B
    that airborne sulfates are Remaining source text redacted.
    Why choice B is not credited

    (B) Do you remember reading that airborne sulfates were the main greenhouse gases?

    Probably not. If you don't remember reading this, it's best to table this answer choice and check the remaining until you find one you recall reading. Experienced test-takers might even feel comfortable eliminating this outright since the word "main" denotes that sulfates are the most prevalent greenhouse gas. Such test-takers would probably conclude that they'd remember a superlative claim like that if the passage had made one.

    If you decided to review this answer choice, you wouldn't find any support. Sulfates were discussed with greenhouse gases, but we're told sulfates counteract greenhouse gasses (P2, S3). Thereefore, sulfates are not themselves greenhouse gases.

  3. C
    the usual duration of Remaining source text redacted.
    Why choice C is not credited

    (C) Do you remember reading how long one cycle of solar energy output takes?

    Probably not. If this detail doesn't sound familiar, it's best to table this answer choice and check the remaining until you find one you remember.

    If we did decide we needed to review this answer choice, we'd find that the author mentions a "decade-to-decade correspondence" between the atmospheric temperature and solar energy variations (P3, S2). However, the author does not provide the average duration of a cycle of solar energy.

  4. D
    predictions as to the Remaining source text redacted.
    Why choice D is not credited

    (D) Do you remember reading about predictions of the effects of global warming on ice?

    Probably not. If this doesn't ring the old memory bell, we recommend tabling this answer choice and checking the rest until you find you can recall.

    If we did review the passage to check (D), we wouldn't find any support. This passage focuses on collaborating the greenhouse theory with current and past temperature data. In other words, the passage doesn't address the future.

  5. E
    an example of a Remaining source text redacted.
    Why choice E is not credited

    (E) Do you remember learning about an example of a technological source of airborne sulfates?

    This is a popular answer choice. Clearly, many testers think they recall this detail. If this does seem familiar, we should review the second paragraph to see if we can find an example of a technological source of airborne sulfates.

    Upon review, we'll see that the second paragraph provides an example of a natural source of airborne sulfates but only mentions that technological sources exist (P2, S3).

What this tests

Question analytics

Based on historical answer selection rates for this question.

Answer choice distribution

  1. A Credited 88%
  2. B 3%
  3. C 3%
  4. D 3%
  5. E 3%

Deeper help

Ask follow-ups on any step

Optional AI tutor mode will let you interrogate assumptions, compare answers, and drill weak patterns without leaving the page.

Human-written explanations stay primary; AI is an add-on when you want it.

Discussion

No threads yet—be the first to ask a question or share an approach.

View all discussions Start a discussion