This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General anatomy, Subject name: Anatomy
[{'content': 'Drugs used for rare diseases are known as \nSelect and explain. \nA. Orphan drugs, B. Rare drugs, C. Radioactive isotopes, D. Alkylating agents', 'role': 'user'}, {'content': 'Answer: A \nExplanation: An orphan drug is a pharmaceutical agent developed to treat medical conditions which, because they are so rare, would not be profitable to produce without government assistance. The conditions are referred to asorphan diseases Refer 6/e p6', 'role': 'assistant'}]