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
Histopatholoty of a lung cancer shows 'clara cells' probable diagnosis is - 
Select and explain. 
A. Squamous cell cancer, B. Bronchio alveolar cancer, C. Large cell cancer, D. Papillary carcinoma
B: Bronchio alveolar cancer
Answer: B: Bronchio alveolar cancer 
Explanation: Ans. is 'b' i.e., Bronchio alveolar cancer "Ultrastructurally bronchoalveolar carcinoma are a heterogenous group, consisting of mucin secreting bronchiolar cells clara cells or rarely type II penumocytes".