Question

Directional selection ______.

Options

• eliminates uncommon forms of alleles

• shifts allele frequencies in a steady, consistent direction

• favours intermediate forms of a trait

• works against adaptive traits

Answer 1

Directional selection shifts allele frequencies in a steady, consistent direction.

Explanation: 

Directional selection occurs in response to gradual changes in environmental conditions, causing a shift in allele frequencies toward one phenotypic extreme. It produces a steady change in the gene pool by favoring certain alleles, leading to evolutionary change in a consistent direction. This type of selection is the basis of artificial selection and helps populations adapt to new environmental conditions.