Happy to help! You mention that you were debating between several other answers in addition to D—which other ones were the most tempting to you?
In the stimulus, the author states that the labeling of otherwise high calorie foods as "sugar free" should be prohibited by law. The support for this conclusion is that many consumers who need to lose weight will interpret the label "sugar free" as meaning "low in calories" and will thereby harm themselves by building their weight-loss diets around these "sugar free" foods. The stimulus also states that manufacturers of sugar free foods are aware of this tendency of consumers.
The question stem asks us to select a principle that, if established, most helps to justify the conclusion. This is question is close to being a strengthen with a sufficient premise, but it doesn't quite need to validate the argument since the stem asks for the answer that most helps to justify the conclusion. The argument structure is A - >B, where A is "If sugar free labels are misinterpreted by consumers" and B is "sugar free labeling should be prohibited by law," which is what we identified as the premise and conclusion in our analysis of the argument. In the answer choices, we're looking for one that paraphrases this A - ->B structure we've identified.
Answer A is incorrect because it states "product labels that are literally incorrect." We can dismiss this answer just by reading this because nowhere in the stimulus does it mention a literally incorrect label. The stimulus suggests that the label is correct, as the "sugar free" label is based on the replacement of all sugar by artificial sweeteners. From this, we know that the stimulus is describing a literally correct label. We can eliminate this answer.
Answer B is incorrect for the same reason as answer A, as it states "product labels that are literally incorrect." We can dismiss this answer just by reading this because nowhere in the stimulus does it mention a literally incorrect label. The stimulus suggests that the label is correct, as the "sugar free" label is based on the replacement of all sugar by artificial sweeteners. From this, we know that the stimulus is describing a literally correct label. We can eliminate this answer.
Answer C is incorrect because even though it corrects the error made in answers A and B, it discusses labels that cannot be interpreted by the average buyer of the product without expert help. There is no information in the stimulus that discusses expert help or the average consumer's inability to interpret product labels without expert help, so this answer is irrelevant.
Answer D is correct. It says, "product labels that are literally correct but will predictably be misinterpreted by some buyers of the product to their own harm should be prohibited by law" This answer correctly describes the labels as literally correct and also contains the premise and conclusion of the argument in the stimulus in A - ->B form, as A is "product labels that are literally correct but will predictably be misinterpreted by some buyers of the product to their own harm" and B is "should be prohibited by law." This principle helps us justify the conclusion in the passage, and this is our answer.
Answer E is incorrect because it describes product labels that are literally correct but "only on one of two equally accurate interpretations" having to be prohibited by law. However, nowhere in the stimulus is there a mention of the equal accuracy of two interpretations of the product labels, so we can eliminate this answer. Interpretations of the labels in the stimulus as high calorie and sugar free are both correct, so this is an incorrect answer.
Hope this helps. Let us know if you have more questions!
