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: Microbiology
[{'content': 'Superantigen causes - \nSelect and explain. \nA. Polyclonal activation of T-cells, B. Stimulation of B cells, C. Enhancement of phagocytosis, D. Activation of complement', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]