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': 'Forty eight hours after sustaining a blunt abdominal injury, a 15 year old boy presents with hematuria and pain in the left side of abdomen. On examination, he has a pulse rate of 96/ minute with a BP of 110/70 mmHg. His Hb is 10-8 gm% with a PCV of 31%. Abdominal examination revealed tenderness in left lumbar region but no palpable mass. The most appropriate investigation to diagnose and find the extent of renal injury would be- \nSelect and explain. \nA. Sonographic evaluation of abdomen, B. Intravenous pyelography, C. Contrast enhanced computed tomography, D. MR urography', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]