LSAT 5 | Section 3 | Logical Reasoning: Q6

LR Question 6 Explanation

QUESTION TEXT: As air-breathing mammals, whales must once have lived…

QUESTION TYPE: Strengthen

CONCLUSION: Whales must once have lived on land and had hind limbs capable of supporting their weight.

REASONING: Whales are air breathing mammals. They have remnants of a pelvis. We have also found a fossilized whale skeleton with fragile hind limbs.

ANALYSIS: To support this, we’ll want to find evidence that shows whales were once on land, or had a skeletal structure capable of supporting hind limbs.

___________

1. CORRECT. A full pelvis would be more capable of supporting strong hind limbs. This shows that in the past whale were more likely to have had strong hind limbs.
2. This shows there is a lack of evidence for our conclusion. It doesn’t strengthen it.
3. This casts doubt on our supporting evidence. Certainly doesn’t help the conclusion.
4. This shows that whale wouldn’t necessarily have required hind limbs to function on land. This weakens the conclusion that they had hind limbs.
5. This doesn’t really tell us anything. Whales don’t have any visible indications of hind limbs either. They only have a half-pelvis.

Recap: The question begins with “As air-breathing mammals, whales must once have lived”. It is a Strengthen question. Learn more about LSAT Strengthen questions in our guide to LSAT Logical Reasoning question types.