Necessary AssumptionDiff: Hardest
Logic Breakdown
Passage Summary: A chef usually uses cornmeal to get sand out of mussels, but since farm-raised ones don't have sand, the chef thinks the cornmeal isn't needed at all.
Conclusion: The chef can safely omit the cornmeal cleaning step when preparing farm-raised mussels.
Reasoning: Cornmeal is used specifically to purge sand from mussels, and since farm-raised mussels do not contain sand, the step is unnecessary.
Analysis: The chef is assuming that the only reason to ever use cornmeal is to remove sand. If cornmeal served a secondary purpose—perhaps it seasons the meat or improves the texture—then the chef's conclusion that the step can be skipped would be invalid. To find the necessary assumption, look for a statement that confirms cornmeal has no other essential function in the recipe. If you negate the correct answer (e.g., 'Cornmeal is actually needed for flavor'), the chef's argument should completely fall apart.
Conclusion: The chef can safely omit the cornmeal cleaning step when preparing farm-raised mussels.
Reasoning: Cornmeal is used specifically to purge sand from mussels, and since farm-raised mussels do not contain sand, the step is unnecessary.
Analysis: The chef is assuming that the only reason to ever use cornmeal is to remove sand. If cornmeal served a secondary purpose—perhaps it seasons the meat or improves the texture—then the chef's conclusion that the step can be skipped would be invalid. To find the necessary assumption, look for a statement that confirms cornmeal has no other essential function in the recipe. If you negate the correct answer (e.g., 'Cornmeal is actually needed for flavor'), the chef's argument should completely fall apart.
Passage Stimulus
Passage Redacted
Unlock Full Passage25.Which one of the following is an assumption required by the chef's argument?
Correct Answer
E
E ties the chef’s specific mussels to the population described in the premise (those from seafood markets). Without that link, the claim “they’re farm-raised and thus have no sand” doesn’t necessarily apply, so the conclusion to skip the sand-removal step is unsupported. Negation test: if the chef’s mussels did not come from a seafood market, the reasoning collapses, showing E is necessary.
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