Logic Breakdown

Passage Summary: Wild potatoes are normally dangerous because of a toxin in their skin, but if you peel them, they become just as safe as regular store-bought potatoes.

Conclusion: A peeled wild potato is just as safe to eat as an unpeeled domesticated potato of equal size.

Reasoning: Solanine is poisonous and concentrated in the skin; wild potatoes have higher total solanine levels than domesticated ones.

Analysis: This is essentially a math problem regarding the distribution of toxins. We know wild potatoes have 'poisonous levels' and domesticated ones have 'very small amounts,' with most of it residing in the skin. To guarantee the conclusion, we need a premise that ensures the amount left in the flesh of the wild potato is less than or equal to the total amount in the domesticated one. Look for an answer that provides a definitive ratio or limit on the solanine remaining after the skin is removed.

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9.

Which one of the following, if assumed, allows the conclusion above to be properly drawn?

Correct Answer
C
C provides exactly the missing comparison: after peeling, the wild potato’s total solanine is no more than the unpeeled domesticated potato’s solanine (same size). With that, the conclusion that peeled wild potatoes are at least as safe follows logically.
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