What mechanism is primarily responsible for the genetic variation seen in populations?

The correct answer reflects the fact that all listed mechanisms contribute significantly to genetic variation within populations.

Mutation serves as a foundational source of genetic diversity, introducing new alleles into the gene pool due to changes in DNA sequences. This process can create entirely new traits that may be beneficial, harmful, or neutral, thereby influencing the evolution of a species.

Genetic recombination occurs during sexual reproduction, specifically in the process of meiosis, where chromosomes pass through one another and exchange genetic material. This shuffling of genes helps create new combinations in offspring, leading to variations among individuals within a species.

Natural selection acts on this genetic variation by favoring individuals with traits that confer an advantage in a particular environment, leading to those traits becoming more common in the population over time. It is an evolutionary process that relies on the inherent genetic variability brought about by mutation and recombination.

Together, these mechanisms interact to produce and maintain genetic diversity, making them all crucial for understanding the variation seen in populations.