Question Type:
Necessary Assumption
Stimulus Breakdown:
Conclusion: Talking on a cell while driving is more dangerous than talking to a passenger.
Evidence: Conversational partner on the phone can't see when things get dangerous, whereas parter in the car usually gets quiet/helpful when things get dangerous.
Answer Anticipation:
We seem to be assuming that it's dangerous if someone's still talking to you while you're driving through a dangerous situation. And we're assuming it's less dangerous if your conversational partner gets quiet or says helful things while you're driving through a dangerous situation.
Correct Answer:
A
Answer Choice Analysis:
(A) This seems pretty accurate. "If your conversational partner isn't providing helpful warnings, then hearing from them during a difficult patch of driving makes things more dangerous." That matches the thinking of the author. She clearly thinks the person you're talking to should shut up when the driving gets tough, or else it's more dangerous, but she also leaves room for the idea that the person you're talking to may abandon the conversation but say something helpful about the dangerous driving situation.
(B) This is the opposite of the author's thinking. When we negate it, it strengthens. Our author thinks that a driver who's talking IS substantially more dangerous than a driver who's not talking.
(C) The author isn't discussing or assuming anything about what people "believe".
(D) STRONG wording red flag: "as likely as". Beyond it being too exact to be necessary, this idea would undercut the author's thinking. He thinks that in a dangerous driving situation, it's better to be talking to someone IN the car (because they'll shut up or say something helpful). If their attempt to say something helpful was just as likely to make things worse, it would undercut the idea that THIS is the safer scenario.
(E) We don't know how the author would score this comparison. Her argument is based on the USUAL behavior of passengers (shut up or say something helpful). She would presumably think that the atypical car passenger is more dangerous than the usual one. But she could still believe that talking on a cell phone to a chatty friend is even some bit more dangerous than talking to a chatty passenger in your car.
Takeaway/Pattern: We can tell from the argument that our author thinks the causal-difference-maker of danger is whether your conversational partner keeps on chatting, or gets quiet/helpful. That should get rid of (C) and (D) pretty comfortably. The last three required some more precise analysis. Since (B) and (E) are phrased negatively, they are easy to negate. In each case, the negation actually strengthens the argument. A correct answer, when negated, would badly weaken the argument. It's not wise to negate conditional answers; just diagram them (mentally or physically) and see if they match the argument core.
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