This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Immunology, Subject name: Microbiology
[{'content': 'What enhances multiplication of T cells in culture - \nSelect and explain. \nA. Phytohemagglutinin, B. Chemotactic factor, C. Leukotrienes, D. Prostaglandins', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Phytohemagglutinin: an initiator of mitosis in cultures of normal human leukocytes mainly T-cells Reff: www.mayoclinic.com', 'role': 'assistant'}]