This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Immunity, Subject name: Pathology
[{'content': 'All of the following are true about type 1 HLA except? \nSelect and explain. \nA. Present on APC, B. Activate cytotoxic T cell and kill virus infected cell, C. Present on nucleated cells, D. First line defense mechanism', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Ans. (d) First line defense mechanism(Ref: R 9th/pg 191)a. True; It is present on all nucleated cells including antigen presenting cells as well as plateletsb. True; It activates cytotoxic T cell and kill virus infected cellc. True; It is present on platelets also, which are non- nucleated cellsd. False; It is a part of adaptive immunity (second line defense mechanism)', 'role': 'assistant'}]