Cellular differentiation progressively restricts cell fate because the unexpressed genes in the cell:

If one isolated cells at random from an organism at different times in its development and measured developmental potential as the average number of distinct cell types that the cells could differentiate into, which of the curves shown here would MOST likely result?

Many valuable horticultural varieties of plants, including roses, rhododendrons, junipers, geraniums, and so on, are commonly propagated by inducing roots to form on cuttings taken from branch tips. This method involves cutting a few inches from the tip of a branch and inserting the cut end into moist sand or other substrate. Under the right conditions, roots may form from the cut end, giving a new plant generated from the stem cutting. In what way could this phenomenon be used to argue for or against the "genome reduction" hypothesis for cell differentiation?