Logical reasoning PrepTest 130 · Section 3 · Question 21

Incorrect. The conclusion of the argument is limited to comparing these two approaches over which is healthier, so other approaches are out of scope. If they exist, they wouldn't affect the argument, so this answer is incorrect.

Incorrect. This conditional is based on it being true that lifestyle changes are a healthier way to treat high blood pressure than medication is, but that's the conclusion of the argument, so we can't assume it's true. Since this conditional relies on the conclusion being true to trigger it, it's incorrect.

Correct. Argument or Facts:
Argument

Valid or Flawed:
Flawed

Question Type:
Strengthen with Necessary Premise

Stimulus Summary:
Goal - Reduce blood pressure
Approach 1 - Medication, which works but has unhealthy side effects
Approach 2 - Lifestyle changes (diet, exercise), which works just as well as medication
Conclusion - It's healthier to reduce blood pressure with lifestyle changes than with medication

Answer Anticipation:
The stimulus reaches a comparative conclusion—one method (lifestyle changes) of treating a disease (high blood pressure) is healthier than another (medication). This type of "soft recommendation" requires that the argument establish the criteria by which the judgment will be made, and that it looks at those criteria for the options.

Here, the criterion, or the point of comparison, is which is healthier. Both are noted as treating the disease equally well, so that's a wash. The medication is noted as having unhealthy side effects. However, there's no discussion of potential unhealthy side effects of these lifestyle changes. Since the comparison is incomplete, the argument is assuming that the comparison will be in favor of its "recommended" approach—lifestyle changes. As such, the argument is assuming that any side effects of lifestyle changes that negatively affect health are less severe than the medication's side effects. Let's look for an answer establishing that.

Answer Explanation:
This answer establishes the point of comparison that's relevant to the conclusion and that we identified in our anticipation. If the side effects of these lifestyle changes are more unhealthy than the side effects of medication, then the argument falls apart. Note that the stimulus is a bit broader in talking about lifestyle changes generally, with the two here being examples, but since these two examples are given in the stimulus, they would have to have fewer unhealthy side effects for the argument to work. So would other lifestyle changes that the Doctor would consider falling into this category, but those aren't brought up in this answer.

Key Takeaway:
A comparative conclusion requires two things in the premises—the criteria by which the comparison will be made, and a discussion of that criteria for all things being compared. If you find either of those parts missing, the argument's assumption will deal with it.

Incorrect. This answer is way too broad, applying to many situations outside of the one in the stimulus. It doesn't even mention the side effects!

Incorrect. There's no indication that the two methods in the stimulus do have similar side effects, so this answer doesn't necessarily apply. Additionally, the methods are equally effective. Neither part of this answer matches up with the stimulus.