Question

read the list of words. dermatologist epiderm hypoderm taxidermist pachyderms based on the common root, all of these words relate to medicine transportation. science skin.

Explanation:

The root - "derm" means skin. A dermatologist is a doctor specializing in skin conditions. Epiderm and hypoderm refer to layers of the skin. A toxicodermist studies skin reactions to toxins. Pachyderms originally referred to thick - skinned animals. All these words relate to skin.

Answer:

D. skin