This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General anatomy, Subject name: Anatomy
True about metastatic calcification is 
Select and explain. 
A. Calcium level is normal, B. Occurs in dead and dying tissue, C. Occurs in damaged hea valve, D. Mitochondria involved earliest
D: Mitochondria involved earliest
Answer: D: Mitochondria involved earliest 
Explanation: Ref, Robbins 8/e p38;7/e p41-42,9/e p65