PrepTest 153, Section 1, Question 10

Working the answers

• A

  We aren't told that some nonhuman cause must contribute to any future decline. The discussion of human activities doesn't establish what every future decline would or would not involve.

• B

  Farmed salmon can reduce prices, but the writer never compares all ways of lowering prices to establish the best one. A possible effect of introducing farmed fish isn't proof that this is the most effective method.

• C

  A growing contribution to protein supplies doesn't make continued growth indispensable. People could get protein from other foods; the writer doesn't show that fish farming must expand for global needs to be met.

• D

  There is no comparison of consumers' taste perceptions. Having farmed substitutes doesn't establish that most people think the two varieties taste the same.

• E
  Correct

  To feed many farmed fish, people must catch wild fish. Producing one kilogram can require more than one kilogram of wild inputs, and increasing farm output can therefore increase those catches. That gives us a concrete way farming could contribute to overfishing rather than relieve it. This is a possible harmful effect, not a claim that every fish farm necessarily produces that result.