Genetics and the environment both play roles in cell differentiation. Which is the BEST example of an environmental factor influencing cell differentiation?
a.) Cambium cells in the trunk of an apple tree form rings of xylem and phloem annually.
b.) The cells of a chicken embryo divide to form three layers: the ectoderm, mesoderm, and endoderm.
c.) The terminal bud on a runner of a strawberry plant begins growing roots when it contacts the ground.
d.) During meiosis, a single cell divides to form four gametes with half the number of chromosomes that somatic cells have.
