Logical Reasoning

PT4 · S4 · Q6 Lourdes: Dietary fiber is an

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Lourdes: Dietary fiber is an important part of a healthful diet.

In 2-speaker questions, our reading goal is to identify what part of speaker 1's argument speaker 2 is addressing.

Lourdes gives us two facts: fiber is important, and experts recommend 20-35 grams per day. Kyra doesn't dispute these facts, but she does add another fact for us to consider: taking in significantly more fiber interferes with mineral absorption, especially calcium. From that evidence, she draws a recommendation conclusion: the public should be told to cut back on the fiber.

We're tasked with weakening this argument, so we need to start by identifying what's already wrong with it in the form of assumptions made, objections overlooked, or famous flaws. When Kyra recommends instructing the public to cut back on the fiber, she seems to be assuming that the public is already at or above the recommended daily intake. That would be the only logical reason to recommend cutting back. Predict an answer that attacks this assumption.

6.

Which one of the following, if true, most undermines Kyra’s recommendation?

  1. Correct

    Among adults, the average consumption

    Why this is right

    If our current intake is approximately 10 grams per day, we're nowhere near the intake level that could interfere with mineral absorption.

    Skill tested: Weaken · how this choice captures the argument's function is the move to repeat next time.

    79% picked this

  2. The more a food is

    Too Specific: processed food

    The fiber content of specific types of food doesn't impact the conclusion that we should recommend lowering fiber intake.

    14% picked this

  3. Many foodstuffs that are excellent

    Too Weak: many

    This answer is wrong for a variety of reasons and that first word should put us on notice. We need correct answers to Weaken questions to be strong enough to have an impact, and "many" is a very weak quantifier. If we read on, the idea that lots of fiber sources are cheap and easy to source is out of scope, meaning this answer has no impact on our conclusion.

    1% picked this

  4. Adequate calcium intake helps prevent

    Opposite (if Anything)

    Kyra's argument hinges on the idea that too much fiber prevents calcium absorption. Establishing calcium intake as important for our bone health supports her argument, if anything, because it gives us a good reason not to risk messing up our absorption with too much fiber.

    5% picked this

  5. Many foodstuffs that are excellent

    Too Weak: many

    Like answer choice C, this one puts us on notice right out of the gate with that weak quantifier "many." Reading on, popularity is out of scope, so this answer has no impact.

    1% picked this

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