This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Respiratory System, Subject name: Physiology
Normal functional residual capacity is: 
Select and explain. 
A. 2.3L, B. 1.3L, C. 2.9L, D. 4.5L
A: 2.3L
Answer: A: 2.3L 
Explanation: Ans. A. 2.3LLung Volumes MEN WOMENTotal lung capacity 6.4 L 4.9LFunctional residual capacity 2.2 L 2.6 LResidual volume 1.5 L 1.2 LInspiratory capacity 4.8 L 3.7 LExpiratory reserve volume 3.2 L 2.3 LVital capacity 1.7 L 1.4 L