This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Endocrinology and breast, Subject name: Surgery
[{'content': 'A 20 year old male presents with chronic constipation, head ache and habitus, neuromas of tongue, medullated corneal nerve fibers and nodule of 2*2 cm size in left lobe of thyroid. This patient is a case of: \nSelect and explain. \nA. Sporadic medullary carcinoma of thyroid, B. Familial medullary carcinoma of thyroid, C. MEN-2A, D. MEN-2B', 'role': 'user'}, {'content': 'Answer: D \nExplanation: MEN-2A (Sipple Syndrome MEN) MEN-2B (MEN-3) Components Medullary carcinoma thyroid Pheochromocytoma Parathyroid hyperplasia or adenoma Hirschprung&;s Disease Cutaneous lichen amyloidosis Medullary carcinoma thyroid Pheochromocytoma Intestinal ganglioneuromas Mucosal neuromas Megacolon Marfanoid features Defect RET oncogenic (Cysteine codon) Chromosome: 10 RET oncogene (tyrosine kinase domain) Chromosome: 10 Transmission Autosomal dominant Autosomal Dominant Ref: Sabiston 20th edition Pgno: 993,1003', 'role': 'assistant'}]