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
In upper air way obstruction all of the following changes are seen except : 
Select and explain. 
A. Decreased Maximum breathing capacity, B. RV decreased, C. Decreased FEV, D. Decreased vital capacity
B: RV decreased
Answer: B: RV decreased 
Explanation: B i.e. RV decreased