20. Genetic variation leads to genetic diversity in populations and is the raw material for evolution. Biological systems have multiple processes, such as reproduction, that affect genetic variation. They are evolutionarily conserved and shared by various organisms. Which of the following statements best represents the connection between reproduction and evolution? (A) Plants that use sexual reproduction are rare since this type of reproduction in plants does not contribute to genetic diversity. (B) In order to increase genetic diversity for evolution in sexually reproducing organisms, mutations must occur in the zygote after fertilization. (C) Since prokaryotic organisms reproduce asexually, there is no mechanism for them to add genetic diversity for evolution. (D) Sexual reproduction increases genetic variation because random mutations can be shuffled between organisms.