The correct answer is - B. It introduces new alleles into a population.
Explanation:
Gebe flow or migration is the transfer of the genetic material or transfer of genes from one population to another population of the same species. Gene flow is also responsible for the genetic change that leads to evolution.
Gene flow can contribute in various ways such as migration or vertical gene transfer parent to progeny, however, it can lead to evolution directly by introducing new alleles into a population.
