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': 'Deep transverse arrest is most commonly seen in which type of pelvis? \nSelect and explain. \nA. Anthropoid pelvis, B. Android pelvis, C. Gynaecoid pelvis, D. Platypelloid pelvis', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Deep transverse arrest is most commonly encountered in android pelvis. Deep transverse arrest occurs when the fetal head lies in the transverse diameter, deep in the pelvis and there is a considerable delay. Android pelvis is a pelvis with converging side walls, straight sacrum and a narrow sub pubic arch.', 'role': 'assistant'}]