This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General physiology, Subject name: Physiology
All are markers of mitochondria except 
Select and explain. 
A. ATP synthase, B. 5-nucleotidase, C. Glutamate dehydrogenase, D. Creatine kinase
B: 5-nucleotidase
Answer: B: 5-nucleotidase 
Explanation: 5-nucleotidase is a marker in the mitochondria It cleaves 5 - nucleotides Ref:Guyton and Hall textbook of medical physiology 12th edition ,pag number: 20,21,22