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: Medicine
Decreased RBC production is seen in - 
Select and explain. 
A. Intramuscular folate administration, B. Renal failure, C. Post gastrectomy, D. Prosthetic valve hemolysis
B: Renal failure
Answer: B: Renal failure 
Explanation: None