In the term cardiopulmonary, what does cardio refer to?

• A. Exercise
• B. Healthy
• C. Heart
• D. Head

Answer: (C)

Cardio- denotes the heart. In the term cardiopulmonary, the prefix comes from Greek kardia meaning heart, signaling that the heart’s function is the focus alongside the lungs (pulmonary). This term describes the system that involves both the heart and the lungs working together to circulate oxygen-rich blood. While people sometimes use “cardio” to mean aerobic exercise in everyday language, in this context it refers to the heart itself, not the activity. The other options don’t fit because head would be a different prefix (cephalo- or cranio-), and there isn’t a prefix meaning healthy used here.