求助一道GRE阅读题

古川幸

Typically the queen honeybee is mother to all the bees in a hive; after mating with several male drones from other colonies, she lays fertilized eggs that develop into all-female worker bees and lays unfertilized eggs that become all-male drones. When a queen dies, workers often lay unfertilized eggs that hatch into drones. Yet workers rarely reproduce while a queen reigns.

　　According to natural selection theory, a worker would enhance her fitness—or ability to propagate her genes—by hatching her own eggs in addition to or in place of the queen’s. But a typical worker’s fitness would be diminished if other workers’ sons, who have less genetic material in common with the worker, supplanted the queen’s sons (the worker’s brothers). Researchers, testing the hypothesis that workers usually somehow block each other’s attempts to reproduce, put unfertilized eggs laid by workers and by the queen into a hive. Other workers quickly devoured the workers’ eggs while leaving the queen’s eggs alone.

19. The passage best supports which of the following inferences about the fitness of honeybees?

　　(A) Reproduction diminishes any individual honeybee’s fitness.

　　(B) An individual worker’s fitness can be maintained without the individual herself reproducing.

　　(C) A hierarchy of stronger and weaker individuals among the worker bees determines which individuals will reproduce when a queen dies.

　　(D) While a queen reigns, the fitness of the worker bees is increased and that of the drones is diminished.

　　(E) Fitness encourages worker bees to hatch honeybee eggs without regard for the relatedness of the young to the “parent.”

这题选B 表示很不理解
According to natural selection theory, a worker would enhance her fitness --or ability to propagate her genes-by hatching her own eggs in addition to or in place of the queen's. 这句话是不是说worker要么自己产卵要么产的卵取代queen的 这样不都是得reproducing吗？ 我是哪里理解错了吗？ 求大神指导

JessicaB22

B、C、D均未提及，显然不对，A过于绝对，从排除法也可以知道答案是B。
我们再看一下B选项。你的原文定位错了。首先，你定位的这句是个虚拟语气，是说“如果根据自然选择理论，应该是......”，接着后面提到了But，这句才是文章的重点！这句话说worker如果reproduce，她的fitness会diminish，与选项worker不reproduce她的fitness才能maintain一致。
定位很重要哟！加油啦！

alex1128

but后的解释是反对自然选择理论的说话,就可以推出来工蜂fitness的提高和生蛋没有关系,所以B选项推断正确

古川幸

JessicaB22 发表于 2013-12-13 19:22
B、C、D均未提及，显然不对，A过于绝对，从排除法也可以知道答案是B。
我们再看一下B选项。你的原文定位错 ...

嗯嗯 现在想明白了 谢谢啦^^

古川幸

alex1128 发表于 2013-12-14 07:29
but后的解释是反对自然选择理论的说话,就可以推出来工蜂fitness的提高和生蛋没有关系,所以B选项推断正确 ...

嗯嗯 终于想明白啦 谢谢^^