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: Pathology
What is the anemia usually associated with chronic renal failure? 
Select and explain. 
A. Hypochromic, B. Macrocytic, C. Normochromic normocytic, D. Microcytic
C: Normochromic normocytic
Answer: C: Normochromic normocytic 
Explanation: The anemia of chronic renal failure is usually normochromic normocytic. Hematocrit often stas to decrease when the serum creatinine level reaches 200 to 300 mmol/L (2 to 3 mg/dl) or when the glomerular filtration rate has decreased to about 20 to 30 ml/min. The etiology of the normochromic:normocytic anemia is probably a decreased synthesis of erythropoietin by the kidney. Ref: Bargman J.M., Skorecki K. (2012). Chapter 280. Chronic Kidney Disease. In D.L. Longo, A.S. Fauci, D.L. Kasper, S.L. Hauser, J.L. Jameson, J. Loscalzo (Eds), Harrison's Principles of Internal Medicine, 18e.