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': 'Shortest fetal skull diameter is \nSelect and explain. \nA. Bimastoid, B. Submentovertical, C. Submentobregmatic, D. Occipito-fronta!', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans: A (Bimastoid) Ref: Dana textbook of obstetrics 5th ed pg 85Explanation: (See the following figure and table)', 'role': 'assistant'}]