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
Pro-inflammatory cytokines are - 
Select and explain. 
A. IL-1, B. IL-2, C. IL-4, D. All
D: All
Answer: D: All 
Explanation: Ans. is All-`a' i.e.,IL-1;'b' i.e., IL-2;'c' i.e.,IL-4