This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General anatomy, Subject name: Anatomy
Which of the following surface glycoproteins is most often expressed in human hematopoietic stem cells 
Select and explain. 
A. CD22, B. CD40, C. CD15, D. CD34
D: CD34
Answer: D: CD34 
Explanation: Ref Robbins 7/e p670; 9/e p590 CD34 is expressed on pluripotent hematopoietic stem cells and progenitor cells of many lineages