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
Aromatic amino acid is ? 
Select and explain. 
A. Serine, B. Histidine, C. Leucine, D. Tryptophan
D: Tryptophan
Answer: D: Tryptophan 
Explanation: Ans:D.)Tryptophan.CLASSIFICATION OF L-a AMINO ACIDS ON THE BASIS OF SIDE CHAINSAliphatic Side Chains : Glycine, Alanine, Valine, Leucine, IsoleucineSide Chains Containing Hydroxyl (OH) Groups :Serine, Threonine, TyrosineSide Chains Containing Sulphur Atoms :Cysteine, Cystine, MethionineSide Chains Containing Acidic Groups or their amides : Aspaic acid, Asparagine, Glutamic acid, GlutamineSide Chains Containing Basic Groups : Arginine, Lysine, HistidineContaining Aromatic Rings : Phenylalanine, Tyrosine, Tryptophan