PrepTest 102, Section 3, Question 2
A large number of drivers routinely violate highway(37 more words not shown)
Which one of the following(8 more words not shown)
- AA person need(10 more words not shown)
- BMost accidents are(4 more words not shown)
- CA driver seldom(22 more words not shown)
- DMost drivers who(7 more words not shown)
- EEven if the(16 more words not shown)
Reading the argument
A speed limiter doesn't stop someone from weaving recklessly between lanes.
Speeding is a significant factor in most accidents. I can see why preventing it might help. But being involved in an accident isn't the same as being the feature whose removal would prevent that accident. A reckless driver might keep making dangerous decisions even with the car's speed capped.
That's my first concern: will removing speeding actually remove most of the crashes, or could other dangerous behavior still produce them? The conclusion needs a substantial safety effect, not merely a change in the speedometer reading.
What we’re looking for
We're asked for an assumption the argument depends on. Keep the proposed result in view: with the devices installed in all cars, most accidents would be prevented. I'd initially want support for the connection between eliminating speeding and preventing those crashes. Let's see which possible problem the choices address.
Working the answers
- A
Trained mechanics could install every device. The argument concerns what happens once the cars cannot exceed the limit, not whether installation is an easy task for an untrained person. Requiring professional installation wouldn't by itself undermine the predicted effect on accidents.
- B
The argument doesn't need inexperienced drivers to cause most accidents. Experienced drivers could speed or make other dangerous choices too. Whatever the drivers' experience, the question is whether limiting speed would prevent most accidents. B assigns blame to a particular group without supplying the needed connection.
- CCorrect
This identifies a problem different from my initial concern: what if exceeding the speed limit sometimes helps a driver escape a collision? Imagine needing to accelerate out of the path of another car. If the limiter prevents that escape, it could create a danger while removing another one.
The qualification about the other drivers matters. The plan equips all cars, so we shouldn't object merely that someone needs to outrun another speeding driver. C addresses the situation that would remain under the plan: nobody involved is exceeding the limit, yet a driver might need to exceed it to avoid a crash.
The argument relies on that need being uncommon. Otherwise, the proposed restriction could frequently block a way of avoiding accidents, undermining the claimed safety result. C doesn't say such a maneuver is never useful, and it doesn't independently prove that most accidents will disappear. It protects the argument against this particular threat.
- D
Intent doesn't settle the safety effect. A device could stop intentional speeding and accidental speeding alike. The author doesn't need most speeding to be accidental to argue that preventing it would reduce accidents.
- E
Higher fines might work or fail while the devices still produced the proposed result. The argument doesn't say speed limiters are the only possible way to reduce speeding. Whether a different policy would also help isn't required for this policy to help.
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