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
Which of the following is not a contraindication in
the therapy with opioids 
Select and explain. 
A. 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
D: Use in severe constant pain
Answer: D: Use in severe constant pain 
Explanation: None