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: Microbiology
MHC class 1 proteins are not present on 
Select and explain. 
A. Platelets, B. RBC, C. T-cells, D. Macrophage
B: RBC
Answer: B: RBC 
Explanation: MHC class 1 proteins are present on all nucleated cells and platelets.