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: Pathology
Commonest type of lung carcinoma in non smokers is 
Select and explain. 
A. Squamous cell carcinoma, B. Small cell carcinoma, C. Adeno carcinoma, D. Alveolar cell carcinoma
C: Adeno carcinoma
Answer: C: Adeno carcinoma 
Explanation: None