Which of these sentences describe sources and preservation of genetic variation? Select all that apply.

A.) Antibiotic resistance in bacterial populations is caused by natural selection of bacteria that inherit mutations that make them resistant to the antibiotics.

B.)If a cell has two pairs of chromosomes, four kinds of gametes are possible as a result of reshuffling of chromosomes during meiosis.

C.) Crossing-over causes a shuffling of allele combinations during meiosis as the alleles from each parent form new combinations on homologous chromosomes.

D.) During mitosis in eukaryotes, the sister chromatids are separated and distributed to two daughter cells.

E.) When two bacteria are linked during conjugation, the donor cell passes DNA to the recipient cell which causes genetic recombination.