Which combining form indicates relationship to a nerve, nervous tissue, or nervous system?

• A. Dent/i
• B. Noct/i
• C. Diaphor/o
• D. Neur/o

Answer: (D)

The concept here is identifying the combining form that signals a relationship to nerves and the nervous system. neur/o is the combining form that denotes nerves or nervous tissue. It appears in terms like neuritis (inflammation of a nerve), neuron (nerve cell), and neural (pertaining to nerves). The other options point to entirely different meanings: dent/i relates to teeth, noct/i relates to night, and diaphor/o relates to sweating. So neur/o is the one that specifically indicates the nervous system.