Logical Reasoning

PT131 · S2 · Q1 On the Caribbean island

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On the Caribbean island of Guadeloupe, a researcher examined 35 patients with atypical Parkinson's disease and compared their eating habits to those of 65 healthy adults.

Evidence

On the Caribbean island of Guadeloupe, a researcher examined 35 patients with atypical Parkinson’s disease and compared their eating habits to those of 65 healthy adults.

She found that all of the AP → EF patients with atypical Parkinson’s regularly ate the tropical fruits soursop, custard apple, and pomme cannelle.

Whereas only 10 of the AP -most→ EF healthy adults [did not have atypical Parkinson’s] regularly ate these fruits.

Conclusion

From this, she EF -causes→ AP concluded that eating these fruits causes atypical Parkinson’s.

Evaluate

The researcher establishes a correlation between eating the tropical fruit and atypical Parkinson’s disease and then concludes a causal relationship between the two.

1.

Which one of the following, if true, most strengthens the researcher's reasoning?

  1. Correct

    For many of the atypical

    Why this is right

    One shows that when the presumed cause is absent, the presumed effect is absent as well. This strengthens the correlation, which does make the causal relationship more likely to be true.

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

    94% picked this

  2. Of the healthy adults who

    Too Weak

    This is too weak to undermine the correlation between those who regularly eat these tropical fruits and atypical Parkinson’s.

    1% picked this

  3. In areas other than Guadeloupe,

    Weaken

    This makes it less likely that these fruits are the culprit since this weakens the correlation between atypical Parkinson’s and these fruits.

    1% picked this

  4. The 10 healthy adults who

    Weaken

    This makes it less likely that these fruits are the culprit since this weakens the correlation between atypical Parkinson’s and these fruits.

    2% picked this

  5. Soursop, custard apple, and pomme

    Weaken

    This makes these fruits less likely to be the culprit since they contain essential vitamins, something common sense would suggest is healthy.

    2% picked this

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