PrepTest 127, Section 3, Question 25
Chef: This mussel recipe's first step is to(48 more words not shown)
Which one of the following(8 more words not shown)
- ACornmeal is not(11 more words not shown)
- BMussels contain no(4 more words not shown)
- CSprinkling the mussels(7 more words not shown)
- DThe chef's mussel(8 more words not shown)
- EThe mussels the(12 more words not shown)
Reading the argument
The recipe calls for sprinkling live mussels with cornmeal. Is that for flavor, or for cleaning? The next sentence answers: the mussels take it in and eject the sand they contain. Removing sand sounds like a useful reason to keep the step.
The chef says it can be skipped because seafood-market mussels are farm raised and contain no sand. But where did this chef get these mussels? A fact about what seafood markets sell doesn't yet tell us what is on the chef's counter.
There are other questions we could ask. Could the cornmeal remove another contaminant? Could it also affect flavor? Those possibilities might give a reason to keep the step, depending on what it actually does. The most direct missing fact, though, is the source of these particular mussels.
What we’re looking for
The necessary-assumption question asks what the chef's argument requires. I would look for the connection between the seafood-market mussels described in the premise and the mussels being used in this recipe. Without that connection, the chef hasn't established that the stated reason for removing sand doesn't apply.
Working the answers
- A
The chef doesn't need to assume that nobody used cornmeal before the mussels reached the market. They could have been cleaned earlier and still contain no sand now. The argument concerns whether this chef can omit the step at this stage, not what cleaning methods were used beforehand.
- B
This is tempting because another contaminant could give the chef a reason to clean the mussels. But does cornmeal remove that contaminant? Perhaps it would have to be washed off in a different way.
The mussels could contain something other than sand while the cornmeal step remained unnecessary. To bear directly on omitting that step, the other contaminant would need to be one the step removes. B's claim that there are no other contaminants at all is not required.
- C
Cornmeal could change the taste without providing a benefit the chef needs. The effect might be unwanted, unimportant, or otherwise not a reason to preserve the step. The argument doesn't require that cornmeal have absolutely no effect on flavor.
- D
A recent recipe could still include a step appropriate for mussels that contain sand. An old recipe could be used with mussels that don't. The date the recipe was written doesn't establish whether these particular mussels need this cleaning step.
- ECorrect
The argument uses the absence of sand in seafood-market mussels to justify skipping the step for this batch. It therefore relies on the chef's mussels coming from a seafood market. Otherwise, the stated fact about those markets gives us no basis for treating these mussels as sand-free.
That doesn't mean no mussel from another source could be clean. It means this argument needs to connect its particular batch to the source that supplies its evidence.
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