This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Hypersensitivity, Subject name: Pathology
[{'content': 'Which of the following is secreted by classically activated macrophages (M1)? \nSelect and explain. \nA. IL-1, B. IL-2, C. IL-4, D. IL-3', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Classically activated macrophages (M1 cells) produce Interleukin (IL)-1 IL-12 IL-23 Chemokines Reactive oxygen species Nitric oxide Lysosomal enzymes', 'role': 'assistant'}]