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
One of the following condition is not associated with clubbing - 
Select and explain. 
A. Primary biliary cirrhosis, B. Chronic bronchitis, C. Cryptogenic fibrosing alveolitis, D. Central bronchiectasis
B: Chronic bronchitis
Answer: B: Chronic bronchitis 
Explanation: None