Final answer:
The primary function of the epithelium on the bottom of the foot is protection; however, it also plays a role in sensation. It is not significantly involved in absorption, secretion, or selective permeability in this particular location.
Step-by-step explanation:
The function of the epithelium on the bottom of our foot primarily involves protection. The epidermis, which is the outermost layer of the skin and a type of epithelial tissue, serves as a barrier against physical damage such as abrasions, as well as against pathogens like bacteria and fungi. Furthermore, the epidermis of the foot also plays a role in sensation, as it contains sensory receptors that help us perceive pressure and other tactile stimuli. While epithelial tissues elsewhere in the body are involved in absorption, secretion, and selective permeability, the epithelium on the bottom of the foot is not significantly involved in absorption or secretion in the context of the options provided. Therefore, the correct answer is A) Protection, with B) Sensation also being a function specific to the sensory aspect of the epithelium on the foot.