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': 'Which of the following is not a contraindication in\nthe therapy with opioids \nSelect and explain. \nA. Use in head injury patient, B. Use in impaired pulmonary function, C. Use of agonist with mixed agonist-antagonist, D. Use in severe constant pain', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]