This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Immunology, Subject name: Pathology
Cell type that lacks HLA antigen is: 
Select and explain. 
A. Monocyte, B. Thrombocyte, C. Neutrophil, D. Red blood cell
D: Red blood cell
Answer: D: Red blood cell 
Explanation: Class I MHC is expressed on all nucleated cells and platelets Class II MHC is expressed on APCs (macrophages, monocytes and dendritic cells), B- cells, Endothelial cells, and fibroblasts.