This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Pharmacology
[{'content': 'The American Cancer Society recommends annual screening mammography for healthy women older than___________years NOT RELATED-GYN \nSelect and explain. \nA. 30, B. 40, C. 50, D. 55', 'role': 'user'}, {'content': 'Answer: B \nExplanation: .', 'role': 'assistant'}]