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: Gynaecology & Obstetrics
[{'content': 'The current imaging technique of choice for the diagnosis of hydatidiform mole is : \nSelect and explain. \nA. Computed tomography, B. Ultrasonography, C. Plain X-ray abdomen, D. Magneic resonance imaging', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ultrasonography', 'role': 'assistant'}]