Unlike natural selection, genetic drift does not depend on an allele's beneficial or harmful effects. Instead, drift changes allele frequencies purely by chance, as random subsets of individuals (and the gametes of those individuals) are sampled to produce the next generation.
Whenever the sperm and the egg combine, it is possible for one or the other to not split properly and bring 2 of the chromosomes instead of just 1
By looking at the diagram, and my knowledge of Punnett squares, i would say B. 4:16
