请教一道逻辑题GWD11-Q40~多谢大家啦

Hebe88

Parland’s alligator population has been declining in recent years, primarily because of hunting.Alligators prey heavily on a species of freshwater fish that is highly valued as food by Parlanders, who had hoped that the decline in the alligator population would lead to an increase in the numbers of these fish available for human consumption.Yet the population of this fish species has also declined, even though the annual number caught for human consumption has not increased.

Which of the following, if true, most helps to explain the decline in the population of the fish species

     A.The decline in the alligator population has meant that fishers can work in some parts of lakes and rivers that were formerly too dangerous.
B.Over the last few years, Parland’s commercial fishing enterprises have increased the number of fishing boats they use.

C.Many Parlanders who hunt alligators do so because of the high market price of alligator skins, not because of the threat alligators pose to the fish population.

D.During Parland’s dry season, holes dug by alligators remain filled with water long enough to provide a safe place for the eggs of this fish species to hatch.

E.In several neighboring countries through which Parland’s rivers also flow, alligators are at risk of extinction as a result of extensive hunting.
答案是D，但是我看了好几遍，都难以理解为什么这个能够解释fish减少的原因阿~大家一起来讨论哈



B.Over the last few years, Parland’s commercial fishing enterprises have increased the number of fishing boats they use.

C.Many Parlanders who hunt alligators do so because of the high market price of alligator skins, not because of the threat alligators pose to the fish population.

D.During Parland’s dry season, holes dug by alligators remain filled with water long enough to provide a safe place for the eggs of this fish species to hatch.

E.In several neighboring countries through which Parland’s rivers also flow, alligators are at risk of extinction as a result of extensive hunting.
答案是D，但是我看了好几遍，都难以理解为什么这个能够解释fish减少的原因阿~大家一起来讨论哈

sdcar2010

This is a paradox question.  You need to provide a reason to explain the apparent contradiction.  In this case, the number of alligator, which preys on a type of fish, is decreasing.  One would think that since the predator (alligator) is decreasing, the prey (the fish) should flourish or at least keep steady.  However, the stimulus claims that the prey's number is decreasing, hence the paradox.

Answer D says that decreasing number of alligator also decreases the safe places for the fish eggs to hide.  If the eggs hatched decrease, the amount of fish in the next generation will shrink.  This explanation links perfectly the decrease of predator and that of the prey, hence reconciles the paradox.

Hebe88

Thx a lot!!!!!解释得好好！有种it suddenly dawned on me 的感觉！