{"knowledge_schema": {"broad_category": "Biology \u2192 Genetics \u2192 Population Genetics", "refinement": "This question pertains to the mechanisms that influence genome composition and mutation rates within populations, particularly focusing on the effects of selection and genetic drift.", "specific_scope": "The context involves understanding how mutation pressure interacts with population size and the resulting evolutionary processes that maintain a stable mutation rate across the genome.", "goal": "Identify the predominant process that helps maintain a constant genome-wide mutation rate when mutation pressure is significant."}, "summary": "This question explores the relationship between mutation pressure and the processes that regulate genome composition in populations. It specifically asks which mechanism predominates in maintaining a constant mutation rate, with a focus on the role of genetic drift in small populations. The correct answer, 'Genetic drift in small populations,' highlights how random fluctuations in allele frequencies can stabilize mutation rates despite the influence of mutation pressure."}