The correct option is B 24
We as humans have 22 pairs of autosomes, which means 22 different chromosomes. The last pair however, consists of two different chromosomes, the X and the Y, giving us two more different chromosomes. This totals up to 24 different or distinct chromosomes (22+X+Y) . Although females would have only 23 different chromosomes (22+X), a human population in general, would have 24 different chromosomes existing.