I believe you meant 'selective breeding'.
Selecitve Breeding is when say a dog breeder, chooses two prospective parents in hopes of achieveing a superior offspring or offspring with desired traits.
Answer:
FERTILIZATION
Explanation:
Fertilization, the fusion of haploid gametes from two individuals, restores the diploid condition. Thus, sexually reproducing organisms alternate between haploid and diploid stages. However, the ways in which reproductive cells are produced and the timing between meiosis and fertilization vary greatly.