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: Pathology
[{'content': 'Retinoblastoma gene is ,located on chromosome: \nSelect and explain. \nA. 13, B. 14, C. 17, D. 22', 'role': 'user'}, {'content': 'Answer: A \nExplanation: 13', 'role': 'assistant'}]