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
Mixed lymphocyte culture is used to indentify ? 
Select and explain. 
A. MHC class I antigen, B. MHC class II antigen, C. B lymphocytes, D. T helper cells
B: MHC class II antigen
Answer: B: MHC class II antigen 
Explanation: Ans. is 'b' i.e., MHC class II antigen Mixed lymphocyte culture is used to identify HLA H