A cell that can terminally differentiate into any of a number of final cell forms.

Before Mendel, the mechanism by which progeny inherited traits from their parents was poorly, if at all, understood. However, for roughly 150 years following Mendel, research into cellular division and meiosis broadly advanced the understanding of genetics and the role of alleles in variations of characteristics within a population. More recently, the field of epigenetics has greatly expanded the understanding of gene expression and its role in developmental biology.
For each of the following, identify the most likely mechanism that best explains the specific data presented.