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
Magnesium level in blood increases in- 
Select and explain. 
A. Uncontrolled DM, B. Liver cirrhosis, C. Kidney failure, D. Chronic alcoholism
C: Kidney failure
Answer: C: Kidney failure 
Explanation: None