Answer:
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).
The Tundra is a place that should stay undisturbed. If the tundras were destroyed animals, plants, and bugs would have no other place to go. Here is my reasoning right now cities are being built so animals are being pushed further away and they are inhabiting the land. If that land is destroyed a decrease in biodiversity, animals, plants, and bugs will occur.
I believe the answer is C
