PrepTest 155

Correct. Argument or Facts:
Argument

Valid or Flawed:
Flawed

Question Type:
Weaken

Stimulus Summary:
Energy drinks have little calcium but lots of caffeine, which causes calcium to be excreted, and calcium deficiency causes brittle bones. Teens who drink a lot of energy drinks also break more bones. Therefore, the energy drinks are probably the cause of the broken bones.

Answer Anticipation:
The conclusion is causal. The premise is a correlation. This is a correlation vs. causation flaw. To weaken those, we should look for an answer that brings up an alternative cause, suggests reversed causality, or brings up counterexamples of the cause and effect not going together.

Reversed causality doesn't make too much sense here (breaking bones results in drinking energy drinks?), and since it's talking general trends, counterexamples also won't have much of an impact. So the correct answer will probably bring up an alternative cause.

Answer Explanation:
This answer suggests an alternative cause. The broken bones aren't a result of drinking energy drinks, but rather not drinking milk. It weakens the argument.

Key Takeaway:
When the question asks you to weaken a causal argument, you should look for answers that bring up alternative explanations, or counterexamples to the causality, or reversed causality.

Incorrect. This might provide an alternative explanation for why teenagers break more bones than other groups, but it doesn't explain the discrepancy in the stimulus—the different rates of broken bones between teenagers who do and don't drink energy drinks.

Incorrect. This answer is too weak to have much of an impact on the argument. While it does bring up an alternative, it doesn't link it to the seen difference between teens who drink energy drinks and those who don't.

Incorrect. They still all contain caffeine, so this answer doesn't impact the argument.

Incorrect. Since the stimulus specifically tells us that those who drink energy drinks excrete more calcium, it doesn't matter if calcium has the same impact.