This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Haematology, Subject name: Medicine
[{'content': 'Most common symptom of Henoch Schnolein purpura Is ? \nSelect and explain. \nA. Intussception, B. Purpura, C. Edema, D. Vomiting', 'role': 'user'}, {'content': "Answer: B \nExplanation: HSP is a small vessel vasculitis caused by immune complex deposition following an infectious trigger. The usual presentation is with purpura over the buttocks & lower legs,accompanied by abdominal pain,gastrointestinal bleeding, & aharlgia. Reference:Davidson's principles & practice of medicine 22nd edition pg no 1119", 'role': 'assistant'}]