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': 'Shoest skull diameter: March 2013 \nSelect and explain. \nA. Biparietal, B. Mentoveical, C. Bitemporal, D. Bimastoid', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Ans. D i.e. Bimastoid Fetal skull Shoest diameter of fetal skull: Bimastoid (7.5 cm) Largest diameter of fetal skull: Mentoveical (14 cm)', 'role': 'assistant'}]