Which combining form means heat?

• A. Crypt/o
• B. Therm/o
• C. Viscer/o
• D. Enter/o

Answer: (B)

The idea being tested is recognizing a combining form that denotes heat. therm/o is the correct choice because it comes from Greek therme meaning heat and is used in medical terms like thermometer, thermotherapy, and thermoregulation. The other forms refer to different body parts or concepts: crypt/o means hidden (as in cryptography), viscer/o relates to the viscera or internal organs, and enter/o relates to the intestine.