This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Urolithiasis, Subject name: Surgery
[{'content': 'A 23 year old male who is otherwise normal complains of mild pain in his right iliac fossa in a waveform pattern which increases during the night and he becomes exhausted and is admitted in the hospital. On examination there is mild hematuria. Urine examination reveals plenty of RBCs, 50WBCs/hpf. Urine pH is 5.5. Most likely diagnosis is: \nSelect and explain. \nA. Glomerulonephritis, B. Ca-Urinary bladder, C. Ureteral calculus, D. Cystitis', 'role': 'user'}, {'content': "Answer: C \nExplanation: Ans. is 'c' ie. Ureteral calculus The patient's clinical picture is typical of ureteric calculus.Colicky renal pain associated with hematuria is suggestive of ureteric stone although a clot from a bleeding renal tumor can cause the same type of pain.A ureteric calculus pain is almost invariably associated with hematuria.Leukocytes in urine can be seen with urolithiasis.", 'role': 'assistant'}]