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
[{'content': 'Onion skin lesion in vessels is seen in ? \nSelect and explain. \nA. Malignant hypeension, B. Benign hypeension, C. Peripheral vascular disease, D. None', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., Malignant hypeensionIn malignant hypeension, there is concentric laminated thickening of aeriolar wall, onion skinning.", 'role': 'assistant'}]