Logical reasoning PrepTest 137 · Section 3 · Question 16

Incorrect. The concern brought up in the stimulus isn't any issues with helping the endangered species, but rather the impact on nonendangered species. As such, the author could very well believe that these experts know best how to help these species, but they can't do so without hurting others.

Incorrect. If anything, the argument is suggesting that this is a possibility that justifies not messing with the environment so that it doesn't happen.

Incorrect. In believing that helping endangered species will hurt nonendangered species, the argument very much imagines the possibility that saving an endangered species might kill off some nonendangered species (the extreme version of making it harder for them to survive), thus endangering the overall diversity of species. So it doesn't overlook this possibility—it raises it.

Incorrect. There's no comparison of the importance of each endangered species to each other one—the only comparison (implied/assumed) in the argument is between endangered species and nonendangered ones.

Correct. Argument or Facts:
Argument

Valid or Flawed:
Flawed

Question Type:
Errors in Reasoning

Stimulus Summary:
Helping endangered species "invariably" hurts nonendangered species, so wildlife experts shouldn't mess with natural habitats.

Answer Anticipation:
The premise in this argument sets up a conflict between endangered species and nonendangered ones. Helping the former "invariably" hurts the latter. From this, the argument concludes that wildlife management experts shouldn't mess with animal habitats to help those endangered species.

While it's certainly true that helping endangered species isn't a slam dunk since it damages other species, there are times when you have to accept a downside in order to achieve an important goal. There's no indication that the harm done to nonendangered species isn't worth it in order to help save the endangered ones. In ignoring the possibility that the harm here might be acceptable, the argument reaches a flawed conclusion.

The correct answer, then, will likely bring up that the argument fails to consider that the cons of messing with habitats to protect endangered species are outweighed by the pros, and thus it shouldn't be avoided.

Answer Explanation:
This answer highlights the argument's assumption that endangered species don't get a higher priority than nonendangered ones, so it's the correct answer.

Key Takeaway:
Arguments that reach conclusions about what "should" or "shouldn't" be done need to have premises that establish a rule for what someone "should" or "shouldn't" do—usually a principle that describes the situation under which that conclusion is justified. Any argument that reaches such a conclusion without establishing that is flawed, and the correct answer will deal with what the assumed principle is. Here, the assumed principle was that an action that damages nonendangered species—even if it helps an endangered one—shouldn't be done. The correct answer reflected that.