This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General obstetrics, Subject name: Gynaecology & Obstetrics
[{'content': 'Longest diameter of fetal skull is \nSelect and explain. \nA. Biparietal, B. Bitemporal, C. Occipito frontal, D. Mentoveical', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Mentoveical is the longest anteroposterior diameter of the fetal head measuring approximately 13.5cms It is the diameter in brow presentation', 'role': 'assistant'}]