PrepTest 126, Section 3, Question 20
Scientists studying a common type of bacteria have(59 more words not shown)
Which one of the following(9 more words not shown)
- ABacteria of most(5 more words not shown)
- BIt is probably(9 more words not shown)
- CIf bacteria are(12 more words not shown)
- DThe conclusion that(18 more words not shown)
- EIt is likely(8 more words not shown)
Reading the argument
One type of bacteria isn't all types of bacteria.
The scientists studied a common type and found that most bacteria of that type were hibernating at any given time. The microbiologists then generalize to bacteria in general. That's like observing that zebras are black and white and deciding that mammals in general have that coloring. Being one member of a broader group doesn't make something representative of the whole group.
The author raises that same concern. If bacterial types were rather similar, the generalization would be reasonable. But the author says they're extremely diverse and concludes that it is unlikely that most types hibernate regularly. That's the author's response to the earlier conclusion.
What we’re looking for
Now we're identifying the overall conclusion, not deciding whether the author has proved every part of that response. The final sentence includes both a reason and a claim: because bacteria are diverse, the author thinks regular hibernation across most types is unlikely. We want the claim, without replacing it with the microbiologists' opposing view or keeping it conditional.
Working the answers
- A
This gives the microbiologists' broad claim, which the author challenges. The accepted study finding is narrower: it concerns most bacteria within one common type. A expands that to most types and therefore cannot represent the author's conclusion.
- BCorrect
“It is probably not true” restates “it is unlikely.” The author concludes that it is probably not true that most bacterial types hibernate regularly. That is the claim supported, in this argument, by the observation that bacterial types are extremely diverse.
- C
The author doesn't merely say what would follow if bacteria were diverse. The author asserts that they are diverse and uses that asserted fact to reach a conclusion about hibernation. C packages the reasoning as a conditional instead of stating the conclusion the author actually draws.
- D
This is the concession made before the author pushes back: if the types were rather similar, the microbiologists' conclusion would be reasonable. The author then says the types are diverse. D describes the hypothetical situation in which the disputed conclusion would be acceptable, not the author's final position.
- E
The author never narrows regular hibernation to just one type. Doubting that most types hibernate regularly still leaves room for several or many types to do so. “Only one” adds a restriction that the conclusion doesn't state.
More Role/Main Point questions
Learn the LSAT our way
Our platform drills Role/Main Point questions at your level and adjusts as you improve.