D. The umbilicus is caudal to the chin
The terms caudal and inferior are synonymous, meaning "away from the head end or toward the lower part of a structure or the body; below." The umbilicus is caudal (inferior) to the chin.
Biosphere, Ecosystem, Communities, Populations, Organisms, Organ systems, Organs, Tissues, Cells, Organelle.
Answer:
Mutagens, mutation-causing substances