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: Radiology
[{'content': 'Cobra head deformity is characterstic of \nSelect and explain. \nA. Posterior urethral valve, B. Ureterocele, C. Bladder tumor, D. Cytitis', 'role': 'user'}, {'content': 'Answer: B \nExplanation: B i.e. Ureterocele', 'role': 'assistant'}]