This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Pharmacology
Which of the following enzyme acts by a 'Ping-Pong' mechanism? 
Select and explain. 
A. Alanine amino transferase, B. Hexokinase, C. Lactate Dehydrogenase, D. Pyruvate Dehydrogenase
A: Alanine amino transferase
Answer: A: Alanine amino transferase 
Explanation: Ping pong displacement: One or more products are released before all the substrate binds the enzyme