Final answer:
The scenario where 'the most common butterfly wing pattern is selected for' is an example of stabilizing selection, a form of natural selection that favors average phenotypes while selecting against extremes.
Step-by-step explanation:
The scenario in which 'the most common butterfly wing pattern is selected for' corresponds to a stabilizing selection scenario in natural selection. Stabilizing selection favors the average phenotype and selects against the extremes in a population. For instance, if mice live in a forest where the ground is a consistent shade of brown, natural selection would favor mice whose fur color closely matches the ground, and mice with fur colors that are significantly lighter or darker would be more visible to predators and less likely to survive. Those mice that blend in the most effectively would have a higher survival and reproductive success rate, resulting in the decreased genetic variance for fur color in the population over time.