This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Hematology, Subject name: Pediatrics
Which organ is the primary site of hematopoiesis in the fetus before midpregnancy 
Select and explain. 
A. Bone, B. Liver, C. Spleen, D. Lung
B: Liver
Answer: B: Liver 
Explanation: Primary site of gematopoesis in fetus before mid pregnancy is liver. Reference : Ghai essential of pediatrics, eighth edition, p.no:330