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: Pharmacology
[{'content': 'True about the orphan drug is: \nSelect and explain. \nA. Developed for orphans, B. Drugs used very rarely, C. Drugs used for rare diseases, D. Rare drug for common diseases', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Orphan Drugs are drugs or biological products\xa0for diagnosis/treatment/prevention of a rare disease or\xa0condition, or a more common disease (endemic only in\xa0resource-poor countries) for which there is no reasonable\xa0expectation that the cost of developing and marketing it will\xa0be recovered from the sales of that drug.\nThe list includes\xa0sodium nitrite, fomepizole, liposomal amphotericin B, ancrod,\xa0rifabutin, succimer, somatropin, digoxin immune Fab (digoxin\xa0antibody), liothyronine (T3) and many more.', 'role': 'assistant'}]