PrepTest 137, Section 2, Question 2

What we’re looking for

Working the answers

• A
  Correct

  The weapons tests were also keeping poachers away. Closing the range removes that protection and gives poachers an opportunity to enter. Poaching supplies a new source of losses that could make the population fall faster even though testing has stopped.

  That isn't the lingering-weapons explanation I initially considered. It works by showing that the dangerous activity had a protective side effect: people who might kill the camels were staying out. Removing one threat can expose the animals to another.

• B

  This compares the early and late years of testing. We need to compare what happened while the range was operating with what happened after it closed. Learning that testing became less harmful during its operation doesn't explain the faster decline afterward.

• C

  This is tempting because it resembles the lingering-damage prediction. Unexploded bombs could certainly make the land remain dangerous. But those bombs were already there before the range closed. C explains why the danger did not disappear; it doesn't explain why losses accelerated when no new testing was occurring.

  We shouldn't add a claim that more bombs suddenly exploded after closure. That extra change could matter, but C never gives it to us. A supplies a change tied to the closure itself.

• D

  These disease outbreaks occurred while the range was operating. They might explain some losses during that period, but the answer doesn't give us a new or worsening disease problem after closure. It misses the change we're trying to explain.

• E

  Food scarcity made testing more harmful in some years. We aren't told that food became scarcer after the range closed, and testing was no longer occurring then. This relationship between food and testing doesn't account for the later increase in losses.