This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Fetal Skull and Maternal Pelvis, Subject name: Gynaecology & Obstetrics
[{'content': 'Maximum fetal skull diameter is: \nSelect and explain. \nA. Biparietal diameter, B. Mentovertical, C. Occipitobregmatic, D. Occipitofrontal', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans, B. MentoverticalRef: DC Dutta. Chapter fetal skull and maternal pelvis, p85ExplanationAll diameters are as follows:A. Suboccipito-bregmatic 9.5 cmB. Suboccipito-frontal 10 cmC. Occipitofrontal 11.5 cmD. Mentovertical 14 cmE. Submentovertical 11.5 cmF. Submentobregmatic 9.5 cm', 'role': 'assistant'}]