Even the most forceful exhalation leaves air in the lungs; this is called the ___________ and is needed to ___________.
A. tidal volume; acquire adequate O2
B. vital capacity; remove adequate CO2
C. functional residual capacity; keep alveoli patent
D. residual volume; keep alveoli patent
Answer: D
If the answers is incorrect or not given, you can answer the above question in the comment box. If the answers is incorrect or not given, you can answer the above question in the comment box.