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': "In which of the following conditions Bandl's ring is seen? \nSelect and explain. \nA. Undilated cervix, B. Premature rupture of membranes, C. Obstructed labour, D. Injudicious use of oxytocic", 'role': 'user'}, {'content': 'Answer: C \nExplanation: Localized rings or constrictions of the uterus develop in association with prolonged obstructed labors. The pathological retraction ring of Bandl is associated with marked stretching and thinning of the lower uterine segment. The ring may be seen clearly as a uterine indentation and signifies impending rupture of the lower uterine segment. Ref: Cunningham F.G., Leveno K.J., Bloom S.L., Hauth J.C., Rouse D.J., Spong C.Y. (2010). Chapter 20. Abnormal Labor. In F.G. Cunningham, K.J. Leveno, S.L. Bloom, J.C. Hauth, D.J. Rouse, C.Y. Spong (Eds), Williams Obstetrics, 23e.', 'role': 'assistant'}]