What part of the reproductive system is highlighted below?
O A. Urethra
O B. Vas deferens
O c. Seminal vesicles
O D. Epididymus

genetic variation can be caused by mutation (which can create entirely new alleles in a population), random mating, random fertilization, and recombination between homologous chromosomes during meiosis (which reshuffles alleles within an organism's offspring).

i'd have to say the answer is probable the second option "the geosphere interacting with the atmosphere"