試題詳解

60. The same gene that causes various coat patterns in wild and domesticated cats also causes the cross-eyed condition in these cats, the cross-eyed condition being slightly maladaptive. In a hypothetical environment, the coat pattern that is associated with crossed eyes is highly adaptive, with the result that both the coat pattern and the cross-eyed condition increase in a feline population over time. Which statement is supported by these observations?
(A) Natural selection reduces the frequency of maladaptive genes in populations over the course of time.
(B) Polygenic inheritance is generally maladaptive, and should become less common in future generations.
(C) Phenotype is often the result of compromise.
(D) In all environments, coat pattern is a more important survival factor than is eye-muscle tone.
(E) Evolution is progressive and tends toward a more perfect population.