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: Surgery
Relative to filgrastim (G-CSF), sargramostim (GM-CSF) 
Select and explain. 
A. Has greater oral bioavailability, B. Is more likely to cause thrombocytopenia, C. Is more likely to elicit an allergic reaction, D. Stimulates production of a wider variety of hematopoietic stem cells
D: Stimulates production of a wider variety of hematopoietic stem cells
Answer: D: Stimulates production of a wider variety of hematopoietic stem cells 
Explanation: Stimulates production of a wider variety of hematopoietic stem cells GM-CSF has wider biologic activity than G-CSF; it stimulates early myeloid stem cells in addition to cells destined become neutrophils.