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
[{'content': 'Which leukotriene is the adhesion factor for the neutrophil on the cell surface to attach to endothelium-( \nSelect and explain. \nA. B4, B. C4, C. D4, D. E4', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., B4 Note : LTB4 is a chemotactic factor", 'role': 'assistant'}]