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': 'HLA-I is present on ? \nSelect and explain. \nA. All nucleated cells, B. Only on cells of immune system, C. Only on B-cells, D. Only on T-cells', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., All nucleated cells", 'role': 'assistant'}]