LSAT 158 | Section 3 | Logical Reasoning: Q10

LR Question 10 Explanation

QUESTION TEXT: Radioactive elements may have been created when the universe…

QUESTION TYPE: Identify the Conclusion

CONCLUSION: Radioactive elements are still being created today.

REASONING: Most radioactive elements decay within a few million years. Because there are still radioactive elements, they must have been created recently.

ANALYSIS: The first sentence is an alternative possibility – maybe radioactive elements were all created when the universe began. But this is refuted by the author, as shown by the “However” in the next sentence. This second sentence is the conclusion – there must be radioactive elements being created still today.

The author goes on to provide evidence – radioactive elements decay but are still present. The final sentence may have tripped you up, because the word “so” may have been taken as an indicator of a conclusion. But it’s actually a paradox that the author solves with the conclusion – there shouldn’t be radioactive elements still, but there are, so they’re being created.

___________

1. This is an extension of evidence provided by the author, but is not the conclusion.
2. CORRECT. See analysis above.
3. This is a statement offered in support of the conclusion, but isn’t the conclusion.
4. This is a possibility the author acknowledges, but isn’t the conclusion.
5. This is evidence the author uses to support their conclusion, but is not the conclusion.

Recap: The question begins with “Radioactive elements may have been created when the universe”. It is a Identify The Conclusion question. Learn more about LSAT Identify questions in our guide to LSAT Logical Reasoning question types.