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': "Therapeutic index indicates \nSelect and explain. \nA. Drug toxicity, B. Drug potency, C. Drug safety, D. Drug's lethal effect", 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]