Final answer:
The word 'Subcutaneous' refers to something that is beneath the skin, and it is the term that means pertaining to under the skin.
Step-by-step explanation:
The word that means pertaining to under the skin is B) Subcutaneous. The subcutaneous layer, also known as the hypodermis, is the innermost layer of the skin. It consists of a fatty layer that contains blood vessels, connective tissue, and axons of sensory neurons. This layer attaches the dermis to the underlying bone and muscle and provides nerves and blood vessels to the dermis. Another term, intradermal, means within the skin, specifically within the layers of the epidermis and dermis. Epidermal relates to the epidermis, which is the outermost layer of the skin. Lastly, dermatological refers to anything related to the study of the skin and its diseases.