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': '10% Tumour is \nSelect and explain. \nA. Pheochromocytoma, B. Papillary Thyroid Carcinoma, C. Follicular Thyroid Carcinoma, D. Brown’s Tumor', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Pheochromocytomas normally obey the “rule of 10”. Hence, they are also called the “10% tumor”. i.e. 10% of pheochromocytomas are:\xa0\n\nFamilial.\xa0\nMalignant.\xa0\nBilateral.\xa0\nExtra-adrenal.\xa0\nSeen in children', 'role': 'assistant'}]