Final answer:
Apical-basal patterning genes are expressed in the apical, basal, and central regions of meristems in plants, which are involved in the primary growth and differentiation of the plant.
Step-by-step explanation:
Apical-basal patterning genes are involved in the development and differentiation of cells in embryonic regions of plants called meristems. These include the apical meristems found at the tips of stems and roots, which are responsible for primary growth through elongation, and the lateral and intercalary meristems, which contribute to increasing the girth and length of the plant respectively. Based on the role of apical meristems, and their involvement in the growth by elongation and the longitudinal view of the root that reveals the zones of cell division in the apical meristem, the patterning genes are expressed in the apical, basal and central regions, hence the correct answer is D. the apical, basal, and central regions.