Final answer:
Recombination has the most profound effect on the rate of evolution in a large sexual population, as it promotes genetic diversity, which is essential for adaptation and evolutionary processes.
Step-by-step explanation:
The effects of recombination on the rate of evolution are greatest in a large sexual population. This is because sexual reproduction, unlike asexual reproduction, generates genetic diversity through mechanisms such as the random assortment of chromosomes and genetic recombination during meiosis. This diversity provides a wealth of raw material for natural selection to act upon, thereby accelerating the evolutionary process. Populations that undergo sexual reproduction are better equipped to adapt to changing environments due to the varied combinations of genes in their offspring.