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: Pathology
IL-1 & TNF-alpha during inflammation are secreted by? 
Select and explain. 
A. Plasma cells, B. Lymphocytes, C. Activated macrophages, D. Platelets
C: Activated macrophages
Answer: C: Activated macrophages 
Explanation: None