What type of genetic variation can occur due to sexual reproduction?

Sexual reproduction generates genetic variation through several mechanisms, all of which contribute to the diversity of offspring. Independent assortment, segregation, and crossing over are key processes that occur during meiosis, the type of cell division that produces gametes (sperm and eggs).

Independent assortment refers to the random distribution of different alleles during gamete formation. During meiosis, pairs of homologous chromosomes are separated into different gametes. Since the orientation of these chromosome pairs can vary, it leads to many possible combinations of alleles in the resulting gametes.

Segregation is the process during meiosis where alleles for a trait segregate so that each gamete carries only one allele for each gene. This ensures that the genetic material contributed by each parent is mixed with the other, allowing offspring to inherit variations from both.

Crossing over occurs during prophase I of meiosis, where homologous chromosomes exchange segments of genetic material. This exchange can create new combinations of alleles on each chromosome, further increasing genetic diversity.

Each of these processes plays a crucial role in enhancing genetic variation in sexually reproducing organisms. Therefore, all of these mechanisms together contribute to the diversity found in populations, making "all of the above" the correct answer.