The correct answer is A. Individuals moving into population.
Gene flow is the movement of genes from one population to another. It can occur through migration, interbreeding, or the exchange of gametes. Gene flow is important because it helps to maintain genetic diversity within populations. It also allows new genes to enter a population, which can lead to evolutionary change.
Option B, genetic drift, is the change in the frequency of a gene variant in a population due to random sampling. Genetic drift is most important in small populations, where it can lead to the fixation or loss of a gene variant.
Option C, mutation, is a change in the genetic material of an organism. Mutations can be caused by errors in DNA replication, exposure to radiation, or chemicals. Mutations can be beneficial, harmful, or neutral.
Option D, artificial selection, is the process of selecting for certain traits in a population. Artificial selection is used by humans to breed plants and animals for desired traits.
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