LSAT 154 | Section 4 | Logical Reasoning: Q26

LR Question 26 Explanation

QUESTION TEXT: Current evidence indicates that there is no methane…

QUESTION TYPE: Sufficient Assumption

CONCLUSION: If there is no methane, then there is no life on Planet 253.

REASONING: Microbes produce methane. If there is no methane, then there are no microbes.

ANALYSIS: This argument is missing the connection between microbes and life. We have the following conditional statements:

If no methane ➞ no life

If microbes ➞ methane

(contrapositive: no methane ➞ no microbes)

All that’s missing is a link that says:

if no microbes ➞ no life

___________

1. The stimulus employs conditional statements so we don’t need to actually establish that this is true.
2. Being able to detect its presence is not mentioned in the stimulus.
3. “Never” is extreme and the conditional statements we’re given wouldn’t trigger this condition.
4. CORRECT. This matches our prephrase exactly.
5. This is an illegal negation of our conclusion. This says, “if methane ➞ life”.

Recap: The question begins with “Current evidence indicates that there is no methane”. It is a Sufficient Assumption question. Learn more about LSAT Sufficient questions in our guide to LSAT Logical Reasoning question types.