Final answer:
Meiosis is the process that leads to the most genetic variation in sexually reproducing organisms through genetic recombination.
Step-by-step explanation:
The process that leads to the most genetic variation in sexually reproducing organisms is meiosis. Meiosis is a type of cell division that produces haploid cells, which have half the number of chromosomes as the original cell. During meiosis, genetic recombination occurs through two processes: crossing over and independent assortment. Crossing over happens when homologous chromosomes exchange genetic material, while independent assortment results in the random arrangement of chromosomes during cell division. These processes create unique combinations of genes in offspring, leading to increased genetic variation.