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
Cryptogenic organising pneumonia is characterised by all of the following except - 
Select and explain. 
A. Migratory pulmonary opacities, B. Obstructive pattern of pulmonary function, C. Arterial hypoxemia, D. Good response to corticosteroids
B: Obstructive pattern of pulmonary function
Answer: B: Obstructive pattern of pulmonary function 
Explanation: None