PrepTest 140, Section 1, Question 5
Essayist: If Earth's population continues to grow geometrically,(96 more words not shown)
Which one of the following(10 more words not shown)
- AIf Earth's population(22 more words not shown)
- BDue to the(15 more words not shown)
- CIf Earth's population(36 more words not shown)
- DThe population of(22 more words not shown)
- ELearning how to(15 more words not shown)
Reading the argument
Moving people off Earth would make room. How long would that room last?
The opening is conditional: if the population keeps growing geometrically, Earth eventually becomes extraordinarily crowded. We can wonder whether that growth could continue, but the essayist hasn't said that it definitely will. For now, follow the proposed response to that scenario: colonize other planets.
The essayist's objection is that the people who stay on Earth keep multiplying. Suppose Earth has 100 people, half leave, and the remaining 50 double over the next 30 years. We're back to 100. The numbers are just a smaller version of the essayist's example: moving half the population buys time without permanently solving the crowding problem.
What we’re looking for
So the main conclusion is an assessment of colonization: at best, it's a temporary solution. The opening describes the problem, and the final doubling example explains why the proposed solution wouldn't last. We should find the claim those pieces are working to support.
Working the answers
- A
This is the opening conditional, which sets up the overcrowding problem. The essayist then considers a proposed solution and explains its limitation. Restating the problem leaves out that assessment, which is the point of the argument.
- B
This broadly predicts that overpopulation will persist and treats continuing growth as the basis for that prediction. The essayist's specific conclusion concerns how well colonization would solve the problem. B leaves out that proposed solution and doesn't preserve the distinction between assuming continued growth and predicting it.
- C
This does describe people leaving Earth, and it closely matches the final example. But that example is support: half leave, the remaining population doubles, and the crowding returns. The essayist uses that reasoning to establish the broader conclusion that colonization would provide only a temporary solution.
- D
The essayist doesn't predict that geometric growth probably will continue. The argument asks what follows if it does. D changes a condition we are reasoning from into a claim about what is likely to happen.
- ECorrect
Learning to colonize other planets would, at best, solve Earth's overcrowding temporarily. The doubling example explains why: after people leave, continued population growth can fill the available space again. Keep “temporary” in the answer. The essayist doesn't deny that emigration could relieve crowding for a while; the objection is that the relief wouldn't last.
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