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
Pericardial calcification is caused by all except 
Select and explain. 
A. Radiotherapy to the mediastinum, B. Methysergide therapy, C. Anticoagulant therapy, D. Benign pericarditis
A: Radiotherapy to the mediastinum
Answer: A: Radiotherapy to the mediastinum 
Explanation: Ans. Radiotherapy to the mediastinum