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': 'In brow presentation, presenting diameter  is/are: \nSelect and explain. \nA. Submentovertical, B. Occipitofrontal, C. Mentovertical, D. Suboccipitobregmatic', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]