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': 'Opsnins is - \nSelect and explain. \nA. C3a, B. 1gM, C. Carbothydrate binding proteins, D. Selections', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., C3a Opsonin o A Substance capable of enhancing phagocytosis. o Complement (C3a) and antibodies are the two main opsonins.", 'role': 'assistant'}]