The frequency of a mutant gene in a population would be likely to increase if:

Explanation

The correct answer is that the frequency of a mutant gene in a population is likely to increase if the gene is selectively advantageous. Such genes confer benefits that enhance an organism's survival or reproductive success, leading to a higher likelihood of being passed on to future generations. This natural selection process causes the gene's frequency to increase over time.Option B is incorrect because dominance does not inherently affect a gene's frequency. Option C is incorrect because the sex-linkage of a gene does not influence its frequency increase. Option D is incorrect because population size alone does not impact gene frequency; it is the selective advantage of the gene that plays a key role.