Which root refers to ganglion?

• A. Dermat/o
• B. Irid/o
• C. Enter/o
• D. Gangli/o

Answer: (D)

The concept tested is identifying the combining form that names a ganglion. A ganglion is a knot or cluster of nerve cell bodies outside the brain and spinal cord, so the combining form that refers to it is gangli/o. That root appears in terms like ganglionic or ganglion cyst, which shows it specifically means ganglion. The other roots point to different parts: dermat/o = skin, irid/o = iris of the eye, enter/o = intestine. So gangli/o is the one that denotes ganglion.