Which of the following statements best describes genetic variation?

Genetic variation is essential to the process of evolution because it provides the raw material for natural selection. Without genetic variation, there would be no differences among individuals within a population for natural selection to act upon. This variation can arise from mutations, gene flow, and sexual reproduction, leading to differences in traits that may offer advantages in survival and reproduction.

When environmental conditions change, those individuals that possess advantageous traits are more likely to survive and reproduce, passing those traits on to the next generation. Over time, this can lead to the adaptation of species to their environments. Thus, the presence of genetic variation is fundamental for populations to evolve and adapt in response to changing environments.