What are the three ways which can produce variant genotypes in the environment?

(N/A) The three primary ways that produce variant genotypes in a population are:
$(i)$ Gene mutations: These are sudden,stable changes in the $DNA$ sequence that create new alleles.
$(ii)$ Crossing over (recombination): This occurs during meiosis,where homologous chromosomes exchange genetic material,leading to new combinations of genes.
$(iii)$ Hybridisation: This involves the crossing of two genetically different individuals,which results in offspring with new combinations of parental genes.