This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Respiratory system, Subject name: Anatomy
Least common cause of clubbing 
Select and explain. 
A. Adenocarcionma, B. Squamous cell carcinoma, C. Small cell carcinoma, D. Mesothelioma
C: Small cell carcinoma
Answer: C: Small cell carcinoma 
Explanation: Clubbing is most common with adenocarcinomaand is least common with small lung cell cancer... Ref:Ptinciples and practice of lung cancer Pg 348