Logical reasoning PrepTest 135 · Section 2 · Question 11

Incorrect. This answer is the negation of the principle we're looking for. The stimulus concludes that this strategy shouldn't be implemented at this time, and this answer provides a sufficient condition for implementing it now.

Correct. Argument or Facts:
Argument

Valid or Flawed:
Flawed

Question Type:
Strengthen (Principle)

Stimulus Summary:
Goal - Counteracting the greenhouse effect
Approach - Spread iron particles around the oceans
Problem with approach - The effect on oceans (an important research) of iron seeding haven't been studied
Conclusion - We shouldn't spread iron particles in the ocean. . . yet

Answer Anticipation:
This Goal/Approach passages reaches a conclusion that the approach suggested—iron seeding the oceans—shouldn't yet be attempted. Why not? Because it messes with an important resource, and the effects of it aren't fully known.

Since this is a Strengthen (Principle) question, we need an answer that connects the details to the judgment in the conclusion. So the answer here should be something like:
If the effects of a strategy that affects an important resource are unknown, then that strategy shouldn't be done yet/should be studied further before being implemented.

Answer Explanation:
This answer allows the conclusion to be drawn that a strategy shouldn't be implemented ("is impermissible"), so it can justify the conclusion. To reach that conclusion, this answer establishes as sufficient that the consequences of the strategy aren't adequately understood. Since the stimulus notes that the side effects of the study have yet to be studied, that guarantees that they're not adequately understood, and thus this answer justifies the conclusion.

Key Takeaway:
When you're in a Strengthen (Principle) question, the goal isn't to strengthen the conclusion—it's to strengthen the argument. As such, it's important that the correct answer reflects a connection between the premises the author relies on and the conclusion, not just any information that is true and the conclusion.

Incorrect. Since the consequences haven't been studied, it's unclear if the consequences are more serious than the problem, so we don't know if this principle applies.

Incorrect. This answer choice justifies the conclusion of not implementing the iron-seeding strategy, but it doesn't do so based on the reasoning of the stimulus. There, the lack of knowledge of the side effects justifies caution, not the simple fact that it alters an important resource (although that it does that is established, it's not the reason for the conclusion).

Incorrect. While the stimulus notes that the side effects of the iron-seeding strategy haven't been studied, and thus it's possible that it would make global warming worse, that possibility isn't mentioned in the premises, so this answer doesn't align with the argument made in the stimulus itself.