PrepTest 105

[lcid:3517] Prep Test 105 LSAT — Logical Reasoning — S2 Logical reasoning

Question prompt

Chronic back pain is Remaining source text redacted.
Why the credited answer is right

Credited answer: E

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

Argument or Facts

Facts

Valid or Flawed

NA

Question Type

Must Be True Questions

Stimulus Summary

Chronic back pain is usually caused by herniated/degenerated disks Most damage happens years before pain starts 20% of those over 30 have damage but no chronic back pain If pain develops, it’s usually because of lack of exercise (ab/spinal muscle deterioration)

Answer Anticipation

This is a weird Must be True question. There are a lot of quantifiers and statements that feel conditional, but there’s never a point where it feels as if the statements are building together as we’d normally see in a question with those features. It also uses a lot of causal language, so it’s not really a conditional argument. All that said, the argument does build together to a certain extent. We know a lot about the causes of chronic back pain, when damage is done, and what turns the damage into pain. So let’s see if we can find an answer that reflects our understanding of those points. Yes, we’re heading in a little blind, but we have a lot of relevant statements to work with.

Answer choices

  1. A
    Four out of five Remaining source text redacted.
    Why choice A is not credited
    There’s no indication that the 80% of those who don’t have disk damage won’t develop that damage later in life. There’s also no indication that some of those 80% don’t already have chronic back pain - the 20% of people have damage without back pain, so some of the remaining might have damage with back pain!
  2. B
    People who exercise their Remaining source text redacted.
    Why choice B is not credited
    Failure to exercise these muscles can turn spinal damage into chronic back pain, but there’s no indication that exercise is a surefire way to avoid back pain. This is treating something that seems necessary in avoiding back pain into something sufficient to avoiding it.
  3. C
    Patients rarely suffer even Remaining source text redacted.
    Why choice C is not credited
    The stimulus talks about disk damage turning into chronic back pain, and that many people with such damage don’t have symptoms of that. It’s possible that when the damage occurs, there’s an immediate flare-up of pain that then subsides until years later when it becomes chronic.
  4. D
    Doctors can accurately predict Remaining source text redacted.
    Why choice D is not credited
    There’s no indication that doctors have the ability to predict back pain. In fact, since insufficient exercise is “generally” what leads to such pain (at least for those in their 30s with disk damage), the doctor would need to predict who will and won’t exercise - and that’s not something within their power to do!
  5. E
    There is a strategy Remaining source text redacted.
    Why choice E matches the stem
    The stimulus notes that insufficient exercise results in disk damage turning into chronic back pain. While that doesn’t mean exercise will prevent such pain - just look at answer choice (B) - but it does mean that getting sufficient exercise might be effective in delaying or preventing the pain by slowing or preventing the deterioration of certain muscles. This is a much weaker version of (B) (“delay” and “can” vs. “sure to be free”), so it’s easier to support. And it is supported by the information in the stimulus, so it’s correct.

What this tests

Discussion

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    Started by ariella

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