33. Which is a TRUE statement concerning genetic variation? (A) It is created by the direct action of natural selection. (B) It arises in response to changes in the environment. (C) It must be present in a population before natural selection can act upon the population. (D) It tends to be reduced by the processes involved when diploid organisms produce gametes. (E) A population that has a higher average heterozygosity has less genetic variation than one with a larger average heterozygosity.