I believe it is D. the genetic variations are in the phenotype of the organism. The reason why I say this is because the phenotype is the physically noticeable characteristics in an organism, this allows them to mutate differently and only the ones who are fit enough and have the best phenotypes will survive.
This cycle is called the carbon cycle.
Zambia
The other three are already well established.
If copies were not made before cell division, than I believe both cells would only have half the proper amount of Chromosomes, as I don't think it's possible for one to have all chromosomes, and another cell to not have any.
