Reading comp PrepTest 150 · Section 4 · Question 19

Passage

Questions 15-20 This passage is based on an article written in 1995.  .       Dowsing is the practice of detecting resources Remaining source text redacted.
Passage walkthrough
Passage Summary

Topic: Science


Paragraph 1

  • Paragraph note
    • Background on dowsing
  • Views, minor Meta-Structures, and the author's attitude
    • Definition of "dowsing":
      • The practice of detecting underground resources by walking with an inert object over a terrain (first sentence)
    • Example of dowsing practice:
      • Dowsers find water by walking with a forked tree branch, and when it is pulled into a vertical position, the water is below (second sentence)
      • The distance and flow rate are also determined via the tree branch (third through last sentences)
    • Cause-and-effect relationship, according to dowsers:
      • Underground water causes the inert object to be "pulled" into a vertical position, with the strength of the pull correlating with the water's flow rate (second and last sentences);(sentence four)

Paragraph 2

  • Paragraph note
    • Dowsing skeptics' view
  • Views, minor Meta-Structures, and the author's attitude
    • List of arguments against dowsing:
      • The crudeness of the method (first sentence)
      • The dowser is probably subconsciously manipulating the results (second sentence)
      • Numerous studies demonstrate that, though some dowsers demonstrate considerable success, most dowsers are not consistently effective (third sentence three)
      • Dowsers usually only discover water where water was likely to be found anyway (last sentence)
    • Cause-and-effect relationship, according to skeptics (in contrast to the cause-and-effect relationship in the first paragraph):
      • Skeptics claim the dowser's subconscious thoughts about the likelihood of finding water cause the inert object to be "pulled" upright (second sentence)

Paragraph 3

  • Paragraph note
    • Dowsing proponents' view
  • Views, minor Meta-Structures, and the author's attitude
    • List of arguments for dowsing:
      • Dowsing is not one skill but multiple techniques that should be evaluated separately (first sentence one)
      • Dowsers are self-certified, and studies of randomly-selected dowsers underrepresent great dowsers (second sentence)
      • Successful dowsers actually notice Earth's electromagnetic fields (third sentence)
      • A good dowser is more effective than scientists using advanced technology (last sentence)

Paragraph 4

  • Paragraph note
    • Author: A recent study shows that dowsers may actually be sensitive to electromagnetic fields and more effective than scientists
  • Views, minor Meta-Structures, and the author's attitude
    • Author's view:
      • A recent study "corroborated" the dowsing proponents' claims that they may be sensitive to electromagnetic fields and may be more successful than scientists using modern methods (first sentence)
    • Comparison, according to the study:
      • In the study, dowsers made consistently more accurate predictions about the location of drill sites for groundwater than geologists and hydrologists (last sentence)
    • Author's attitude: "corroborated" (first sentence); "extensive study" (first sentence); "consistently made significantly more accurate predictions" (last sentence); "suggesting" (last sentence)

Main Point: Although many are skeptical of dowsing's efficacy, a recent study has corroborated some dowsing proponents' claims that skilled dowsers are sensitive to changes in Earth's electromagnetic field and are more effective at locating underground water supplies than geologists or hydrologists.

Key Lines?

Paragraph 1, Sentence 1 (P1, S1) - Definition of practice

P2, S1 - Beginning of argument against the practice

P3, S1 - Beginning of argument for the practice

P4, S1 - Author's endorsement of the practice

Meta-Structure?

Resolving a Debate: This author uses a Resolving a Debate Meta-Structure in this passage. In such a passage, the author describes two sides of a debate and then endorses one side or attempts to resolve the dispute. In this case, the author presents a debate over dowsing's efficacy and eventually supports the pro-dowsing position. The passage is organized straightforwardly: the author defines dowsing in the first paragraph, lists arguments against dowsing in the second, outlines the pro-dowsing position in the third, and then gives their final conclusion based on recent evidence in the last paragraph.

The main point in Resolving a Debate Meta-Structures is the author's opinion on the debate or the author's mediation/reconciliation of the debate. In this case, the author's opinion is squarely pro-dowsing. So, we summarized the main point as follows, "Although many are skeptical of dowsing's efficacy, a recent study has corroborated some dowsing proponents' claims that skilled dowsers are sensitive to changes in Earth's electromagnetic field and are more effective at locating underground water supplies than geologists or hydrologists."

List: The predominant minor Meta-Structure in this passage is a list. The author lists arguments for and against dowsing in the second and third paragraphs. We summarized each item on the list in the Passage Summary. We recommend highlighting or underlining each item to help us locate any item we might need to answer a question. But if you'd like to save yourself some fact-finding missions on the inevitable Minor Point questions, you can try to memorize a few key details. Here's what we recommend memorizing about arguments for and against dowsing:

  • Skeptics say dowsing is ineffective, unsupported by studies, and only used when groundwater is likely to be found anyway.
  • Skeptics concede that some dowsers are consistently successful.
  • Proponents say good dowsers may be sensitive to electromagnetic fields and more effective than scientists with modern technology.
  • Proponents concede that there are many more bad dowsers than good dowsers represented in a typical study.

Of course, if you have trouble memorizing stuff, you don't have to. You can always check the passage to anticipate what the correct answer will say. We'll discuss how you can do this most efficiently in the question explanations.

Last Thoughts?

With the lists factoring into each paragraph, this is an exceptionally detail-oriented passage. So, we should expect a higher proportion of Minor Point questions. Thankfully, we'll be armed with location devices even more powerful than a dowsing stick: our notes, what we highlighted/underlined, and (if necessary) the CTRL/Command + F search function.

Question prompt

The passage provides information Remaining source text redacted.
Why the credited answer is right

Credited answer: D

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 is a variation of a Must Be True question. In this question, each answer choice is, Jeopardy-style, in the form of a question. The correct answer will feature a question that the passage answers. The four incorrect answers will present a question that the passage doesn't answer.These questions generally provide 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 we can't recall the answer to a question in a given answer choice, we shouldn't comb through the passage, searching for an answer. Instead, we'll table that answer choice and move on to the next one. If we can recall the answer to a question — even vaguely — we'll use our notes/highlights/underlines to find the part of the passage that provides the answer. If we can point to the answer in the passage, we'll select that answer choice and move on to the next question.

Answer choices

  1. A
    When was dowsing first Remaining source text redacted.
    Why choice A is not credited

    (A) Do you remember whether dowsing was first employed to locate groundwater?

    Perhaps not. If you can't recall whether the passage answered this, it's best to table this answer choice and move on to the next one. Avoid the temptation to see if the passage answered this question. Instead, only review the passage if you can remember that the passage discussed the topic in question.

    If we did need to review the passage to eliminate this answer choice, we wouldn't find any information about time or chronology. The first paragraph, which provides most of the background information on dowsing, says that dowsing is used to detect "resources or objects beneath the ground" (P1, S1). So, dowsing could have been introduced to locate groundwater, or it could have been introduced to locate some other resource or object.

  2. B
    Is the success of Remaining source text redacted.
    Why choice B is not credited

    (B) Do you remember whether rainfall affects dowsers' success?

    Probably not. If you can't recall whether the passage answered this, move on to the next answer choice. We'll only review the passage when we remember the passage providing an answer to the question.

    If we decided to review the passage to eliminate this answer choice, we wouldn't find any information about rainstorms saturating the ground. Arid landscapes are discussed (P4, S1), and skeptics state that dowsers only found water in water-abundant areas (P2, S4). But there's nothing about rainstorms.

  3. C
    What proportion of successful Remaining source text redacted.
    Why choice C is not credited

    (C) Do you remember what percentage of dowsers use forked sticks?

    Probably not. If you can't remember reading the answer to this, table this answer choice and move along to the next one. We'll save time if we only review the passage when we can recall that the passage furnished an answer to the question.

    If we thought we remembered the answer in the passage and opted to search for that answer, we wouldn't find any information on the proportion of dowsers who use forked sticks. Dowsers' tools are only described in the first paragraph (P1, S1), and that paragraph doesn't tell us the proportion of dowsers who use sticks instead of, say, pendulums or metal rods.

  4. D
    Is dowsing ever utilized Remaining source text redacted.
    Why choice D matches the stem

    (D) Do you remember whether dowsing is used to locate anything other than water?

    Perhaps. If you recall reading about other resources dowsing can locate, it's worth checking the passage to see if you can find an answer to this question. However, if you don't remember whether the passage answers this question, check the next answer choice. You can return to this answer choice if you can't recall whether the passage answered any of the questions in the answer choices.

    If we check the passage, we should review the first paragraph, which provides most of the background information on dowsing. That paragraph states that dowsing can be used to detect "resources or objects beneath the ground" (P1, S1). We wouldn't call water an "object," so it appears some people dowse to find things other than water underground. If we kept looking, we'd also see that the study showed that dowsers can locate dry fracture zones and not just underground water (P4, S4). Therefore, we can find an answer to (D), making it the correct answer.

  5. E
    What are some of Remaining source text redacted.
    Why choice E is not credited

    (E) Do you recall learning about the specific surface clues that indicate the presence of groundwater?

    Perhaps. This is a tricky answer choice that many test-takers select incorrectly. These test-takers probably recall reading the skeptics' claim that dowsers rely on surface clues to guide them to the location of groundwater (P2, S2). However, the passage never specifies what these surface clues are. The study mentions several geological features in various arid countries, including tilted fracture zones, bedrock, and underground dry fracture zones (P4, S2). Still, the author gives us no indication of what a surface clue for underground water might be. 

What this tests

Question analytics

Based on historical answer selection rates for this question.

Answer choice distribution

  1. A 2%
  2. B 8%
  3. C 5%
  4. D Credited 63%
  5. E 22%

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