Question

Scientists documented that the acid tolerance of several plant species has increased significantly in the area with industries like a copper smelter.

This is an example of

a)genetic drift

b)directional selection

c)stabilizing selection

d)disruptive selection

Answer 1

here one extreme phenotype is selected due to the environment changes, copper smelter industries decreases pH in nearby soils, so plants that can grow in the acidic soil are selected.

genetic drift: changes in the allele frequencies due to chance events.

directional selection: one extreme phenotype is selected.

stabilizing selection: intermediate phenotype is selected.

disruptive selection: extreme phenotypes at both ends are selected.

so the answer is b) directional selection.