What is the best definition of directional selection

In population genetics, directional selection is a mode of natural selection in which an extreme phenotype is favored over other phenotype, causing the allele frequency to shift over time in the direction of that phenotype

Directional selection is a mode of natural selection an extreme phenotype is favored over other phenotypes this causes the allele to shift over time in the direction of the favored phenotype

a: the sheep and waste material both release carbon into the atmosphere.

answer; i believe the answer is hydraulic action;