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: Medicine
All statements are true about chronic obstructive pulmonary disease; except 
Select and explain. 
A. FEV1  < 30 of predicted value, B. FEV1/FVC < 0.7, C. Decreased Residual volume, D. Increased total lung capacity
C: Decreased Residual volume
Answer: C: Decreased Residual volume 
Explanation: Spirometric classification of COPD severity based on post-bronchodilator FEV1