Should be A. Species have changed over time.
Mitosis - 48 chromosomes (diploid cells)
Meiosis - 24 chromosomes (haploid cells)
Diploid cells. Meiosis is the process of cell division by which involving gametes. Cell division is just the same for sperm and egg cells, but they have distinguishable descriptions and labels in the process. Spermatogenesis is for the males’ sperm cells and oogenesis is the process for females’ egg cells. The cell division of meiosis involves the two phases, respectively meiosis I and meiosis II. Meiosis I like mitosis is the cell division that produces diploid cells<span>. These diploid cells are cells that contain a complete pair of chromosomes which is 46. The result is two diploid cells after the first meiosis. To provide clear explanation, in contrast haploid cells only contain 23 chromosomes and are created after meiosis II which is 4 in number.</span>
Concordance rates between monozygotic twins vary in different studies, approximately 50%; whereas dizygotic twins was 17%. Some twin studies (Koskenvuo et al; Hoeffer et al) have found rates as low as 11.0%–13.8% among monozygotic twins, and 1.8%–4.1% among dizygotic twins.