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: Microbiology
Least common site of calcified hydatid cyst is ? 
Select and explain. 
A. Lung, B. Mediastinum, C. Extraperitoneal site, D. Liver
A: Lung
Answer: A: Lung 
Explanation: Ans. is 'a' i.e., Lung . The pulmonary hydatid cyst almost never calcify, unlike mediastinal cyst ----> Grainger