This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Abnormal labor, Subject name: Gynaecology & Obstetrics
[{'content': 'Outlet forceps, means: \nSelect and explain. \nA. Head at station "0", B. Full cervical dilatation, C. Rupture of membrane, D. Rotation > 45', 'role': 'user'}, {'content': 'Answer: B \nExplanation: In modern obstetrics outlet and low forceps are commonly used .Kielland is very rarely used today and only by experienced person s(refer pgno:446 sheila textbook of obstetrics 2 nd edition)', 'role': 'assistant'}]