Answer: C. Developing calluses
Explanation:
Our skin is a multilayered epithelium (the epidermis) underlain by a layer of stem cells that give rise both to more of themselves and to keratinocytes, the major cell type in the skin. As keratinocytes move toward the outer surface, they become increasingly flattened and filled with keratin intermediate filaments. The deposition of keratin in the skin can be increased in response to abrasion, producing calluses.
