This is kinda a weird question for me to answer... BUT.... lol
I think it is Meiosis, which occurs over two cycles of cell division, which sperm cells complete before fertilization. It also is the process that creates gametes -- sperm and egg cells -- containing only one, or a haploid, set of chromosomes.
And fertilization is the action or process of fertilizing an egg, female animal, or plant, involving the fusion of male and female gametes to form a zygote... OR
it could be the action or process of applying a fertilizer to soil or land.
Hope this helps. c;