Final answer:
Recombination directly removes linkage disequilibrium in populations by creating new combinations of alleles during the formation of gametes. It does this by exchanging segments of DNA between homologous chromosomes, thereby disrupting the association between alleles that are in linkage disequilibrium. The correct option is D.
Step-by-step explanation:
Recombination is the process that removes or breaks down linkage disequilibrium in populations. Linkage disequilibrium occurs when alleles at two linked loci are associated with each other more often than expected by chance alone.
Recombination during sexual reproduction creates new combinations of alleles by swapping genetic material between paired chromosomes, hence breaking up the associations that contribute to linkage disequilibrium.
In the context of Hardy-Weinberg Equilibrium, certain conditions such as mutation, genetic drift, and nonrandom mating can lead to changes in allele frequencies in a population, thus introducing a departure from the equilibrium.
These mechanisms, along with gene flow and environmental variances, contribute to the microevolution of a population.
Among the given options, Recombination explicitly addresses the breakdown of linkage disequilibrium, and thus is the correct answer.
Other processes such as natural selection, genetic drift, and mutation can influence allele frequencies and can indirectly affect linkage disequilibrium, but recombination directly results in the breakup of pre-existing allelic associations. Option D. is the correct one.