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: Radiology
Well defined lesion in the lung with popcorn calcification on X-ray suggestive of- 
Select and explain. 
A. Ca lung, B. Adenoma, C. Hamartoma, D. Hydatid cyst
C: Hamartoma
Answer: C: Hamartoma 
Explanation: Popcorn calcification is characteristic of Hamartoma.