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
Normal sized to enlarged kidneys in a patient with chronic failure is indicative of - 
Select and explain. 
A. Benign nephrosclerosis, B. Chronic glomerulonephritis, C. Chronic interstitial nephritis, D. Primary amyloidosis
D: Primary amyloidosis
Answer: D: Primary amyloidosis 
Explanation: None