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: Anatomy
[{'content': 'Dose of radiation per study in mammography is \nSelect and explain. \nA. 0.1cGy, B. 0.2, C. 0.3, D. 0.4', 'role': 'user'}, {'content': 'Answer: A \nExplanation: .', 'role': 'assistant'}]