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
The amino acid which on decarboxylation gives rise to a product with potent vasodilator propeies is: 
Select and explain. 
A. Arginine, B. Histidine, C. Glutamate, D. Aspaate
B: Histidine
Answer: B: Histidine 
Explanation: Histamine is derived from the decarboxylation of the aminoacid histidine, a reaction catalyzed by the enzyme L-histidine decarboxylase present in the liver. It is a hydrophilic vasoactive amine. Ref: Neuroscience in Medicine edited by P. Michael Conn, Page 496