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: Biochemistry
Which of the following are derivatives of amino acid Glycine 
Select and explain. 
A. Heme, B. Creatinine, C. Glutathione, D. All of the above
D: All of the above
Answer: D: All of the above 
Explanation: Derivatives of Glycine are:

Heme
Purine ring
Glutathione
Creatine, creatine phosphate, creatinine

Note: Glycine is not a part of pyramidine ring.