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
[{'content': 'Characteristics of BENIGN tumour of lung in X-ray is \nSelect and explain. \nA. Size > 5 cms diameter, B. Cavitation, C. Peripheral location, D. Concentric dense calcification', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Central, concentric, laminar, popcorn or homogeneous (diffuse) calcification is seen in benign lesions.', 'role': 'assistant'}]