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: Surgery
[{'content': 'False about erythema nodosum: \nSelect and explain. \nA. Trunk is the most common site for these lesions, B. The initial lesion is red and later turns blue, C. It can occur in Sarcoidosis, D. The lesions are painful', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Erythema nodosum is characterized by tender, painful. erythematous. nodular eruption commonly over shin bone. Trunk is not affected commonly. On histopathology septal panniculitis is detected. Nodules never ulcerate, regress within 3-6 weeks to leave behind post inflammatory hypes pigmentation.', 'role': 'assistant'}]