The dobzhansky–muller model explains hybrid infertility in crosses between two close species (such as the fruit flies d. simulans and d. melanogaster). which of the following is the best explanation of this model? group of answer choices two species develop strong prezygotic mechanisms of reproductive isolation and mating is less likely to proceed epistatic interactions between the alleles of two or more loci, undergoing different evolutionary paths in the two speciating groups, lead to the fitness costs of hybridization. changes in the numbers of chromosomes cause hybrid zygotes to have lower fitness and often makes them infertile. hybridization between the two sister species is impossible because of the imminent hybrid sterility.