Final answer:
The frequency of the dominant allele can be calculated using the Hardy-Weinberg equation. Given the frequency of the homozygous recessive genotype, we can calculate the frequency of the recessive allele and then the frequency of the dominant allele. The correct answer is D. 0.6.
Step-by-step explanation:
The frequency of the dominant allele can be calculated using the Hardy-Weinberg equation: p² + 2pq + q² = 1, where p represents the frequency of the dominant allele and q represents the frequency of the recessive allele. Given that the frequency of the homozygous recessive genotype (aa) is 0.16, we can calculate q by taking the square root of this frequency: √0.16 = 0.4. Since p + q = 1, the frequency of the dominant allele (p) can be calculated as 1 - q: 1 - 0.4 = 0.6. Therefore, the correct answer is D. 0.6.