Final answer:
Tinea, derived from a Latin word meaning worm, refers to fungal skin infections like ringworm and tinea unguium, which affects the nails.
Step-by-step explanation:
The term derived from a Latin word meaning worm that refers to a group of skin infections caused by fungi is A) Tinea. Tineas, or cutaneous mycoses, are caused by dermatophytes, which are fungal molds requiring keratin for growth. This keratin is found in human skin, hair, and nails. These fungal infections, such as ringworm, present as red rings on the skin and are not actually caused by worms. The term 'tinea' is used to classify various types of fungal skin infections based on the location they affect on the body. For instance, fungal infections of the nail, known as tinea unguium, result in the nail becoming yellow, brittle, and prone to breaking.