Which of the following best defines biological evolution within a population? Select one: a. change in allele frequencies over time b. natural selection c. survival of the fittest d. phenotypic change within an individual’s lifetime

a. change in allele frequencies over time

Explanation:

Biological evolution is defined as the genetic changes from generation to generation.

Biological evolution can also defined as the changes in the inherited traits in a population over successive generation of organisms. Changes in the allele frequencies over a time causes changes in the genetic expression of an organism, which is a key characteristics of biological evolution.

The genetic expression changes from generation to generation during reproduction process and hence different characteristics tend to exist within any given population and shows genetic variation.

Hence, the correct option is a. "change in allele frequencies over time".

because they are eaten by the frog and the frog getseaten by the snake and the snake by the eagle