Final answer:
The suffix in the term onychomycosis is '-mycosis,' referring to a fungal infection affecting the nails.
Step-by-step explanation:
In the term onychomycosis, the suffix is A. -mycosis. The term breaks down into "onycho-" referring to the nail, and "-mycosis," which indicates a fungal infection. Onychomycosis is classified among cutaneous mycoses, which are infections that affect superficial layers of the skin, hair, and nails. These conditions are relatively common and are typically treated with antifungal medications.