PrepTest 109, Section 4, Question 13

Sufficient AssumptionDifficulty5 of 5
The questionFull text in your LawHub copy of PrepTest 109

Politician: The bill that makes using car phones(54 more words not shown)

The argument's main conclusion follows(9 more words not shown)

Reading the argument

I can see the safety argument. Drivers using car phones become seriously distracted, and the proposed ban would deter that behavior. If fewer drivers create that danger, the proposal has a benefit worth considering.

But the conclusion is a recommendation: we should adopt the bill. Facts about a benefit don't, on their own, give us a rule for what legislation should be passed. We may find the recommendation sensible and still recognize that the argument hasn't explicitly supplied that step.

What we’re looking for

The question asks us to make the main conclusion follow. We need to connect the stated safety benefit to the decision to adopt the law. I'd predict a principle saying that a proposed law should be adopted when it reduces a threat to public safety.

Working the answers

  • A

    Paying more attention may make driving safer. That supports the general safety concern, but it doesn't tell us that the government should adopt a law to address it. The missing step is from reducing danger to passing this bill, not from attention to safety.

  • B

    Even if legislation were the only way to reduce this threat, why must we choose that way? “This is the only way to achieve a goal” doesn't, by itself, establish “We should do it.”

    Imagine someone saying that becoming a billionaire would require giving up everything else they care about. Even if that really were the only route, it wouldn't follow that they should take it. They could decide the goal isn't worth the cost.

    Likewise, B doesn't supply a rule requiring the adoption of this bill. We should grant its claimed restriction for purposes of the question, then notice that the recommendation still needs support.

  • C

    The passage already identifies a distraction that threatens safe driving: using a car phone. A general statement that some distractions interfere with safe driving adds no rule about which laws should be adopted. It helps describe the problem without proving the proposed response is required.

  • D
    Correct

    This supplies the missing policy rule: any proposed law that would reduce a threat to public safety should be adopted. The passage tells us that car-phone use creates such a threat and that making it illegal would deter people from doing it. The proposed bill therefore meets D's condition, and the recommendation to adopt it follows.

    The rule is broad. We don't need to endorse it as a complete philosophy of legislation; we need to see that, if assumed, it proves this argument's conclusion.

  • E

    The bill concerns drivers using car phones. A claim about passengers' use doesn't establish that the drivers' use should be illegal. Even if passengers caused no distraction at all, we'd still need the step from the identified danger to the recommendation to pass the bill.

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