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 aminoacids have maximum buffering capacity at PH 7? 
Select and explain. 
A. Lysine, B. Arginine, C. Histidine, D. Glycine
C: Histidine
Answer: C: Histidine 
Explanation: pKa of histidine is 6.5 - 7.4. It allows for maximum buffering capacity at neutral pH.