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: Pharmacology
[{'content': 'The chief advantage of ketorolac over aspirin is that the former : \nSelect and explain. \nA. Can be combined more safely with an opioid such as codeine., B. Does not prolong bleeding time., C. Is available in a parenteral formulation that can be used intramuscularly or intravenously., D. Is less likely to cause acute renal failure in patients with pre-existing renal impairment.', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]