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': '25 year old woman in labor has fetal heart tracing as shown below. What is your diagnosis. She is G2 P1 with prior cesarean delivery \nSelect and explain. \nA. Cord compression, B. Uterus repture, C. Fetal anemia, D. Amniotic fluid embolism', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Fetal heart tracing shows non reassuring FHR pattern with variable heart decelerations that evolve into late decelerations and brady cardia. Rupture apparently stimulated reflex push, after which uterine tone diminished and bradycardia worsened.', 'role': 'assistant'}]