Answer:
The most likely explanation for the increase in the brown-feathered phenotype in tawny owls over the past 28 years is option B: Darker feather color in tawny owls makes them less visible to predators as they sit in the trees.
Step-by-step explanation:
This advantage could lead to increased survival rates and reproductive success for brown-feathered owls, which would in turn increase the frequency of the brown allele in the population over time. Option A is not entirely accurate, as dominance does not necessarily guarantee elimination of a recessive trait from a population. Option C is not supported by the information given and is not a plausible explanation for the increase in brown feathers. Option D refers to a bottleneck event, which is not mentioned in the question stem and is not a necessary component for explaining the increase in brown feathers.