The answers that apply are;
new allele combinations were advantageous in the presence of
parasites with high mutation and reproduction rates.
sexual reproduction increased genetic variability and
survival in a changing environment?
Sexual reproduction increases genetic variability due to combinations of alleles from the parents to the
offsprings. This increases the chances
that a particular combination may be able to confer resistance to the
disease-causing bacteria and hence increase the survival of the roundworms population.
