This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Physiology
The volume of gas in the lungs at the end of normal expiration is: 
Select and explain. 
A. Expiratory reserve volume, B. Functional residual capacity, C. Residual volume, D. Inspiratory reserve volume
B: Functional residual capacity
Answer: B: Functional residual capacity 
Explanation: The volume of the air remaining in the lungs after normal expiration is Functional Residual Volume (FRV).
The volume of the air remaining in the Lungs after forced expiration is Residual Volume (RV).