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: Medicine
[{'content': 'A feature of Renal vasculitis in children is - \nSelect and explain. \nA. IgA raised, B. Antinuclear antibody in serum, C. Low complement level, D. Cytoplasmic antinuclear Ab in serum', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]