Answer:
Selective breeding increases the frequency of favorable gene combinations associated with a particular phenotypic trait
Explanation
Selective breeding, also known as artificial selection, is a method for improving phenotypic traits in plants or animals by mating individuals with specific desirable hereditary traits and then select offspring that have better performance for these traits. This technique is effective only when the parental population used for selection exhibits genetic variability for the trait to be selected. The sheep's wool is a quantitative trait, i.e., a phenotypic characteristic that depends on the cumulative effects of many genes and the environment. In this case, the artificial selection will consist of obtaining sheep with increased production of wool, which is achieved by selecting favorable gene combinations for improved trait performance.