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: Surgery
[{'content': 'Cobra head deformity in the lower end of ureter is seen in: \nSelect and explain. \nA. Ureterocele, B. Vesical diverticula, C. Carcinoma of urinary bladder, D. Urethral stricture', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]