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
Tyrosine utilized in synthesis of all except ? 
Select and explain. 
A. Melanin, B. Melatonin, C. Dopamine, D. Thyroxine
B: Melatonin
Answer: B: Melatonin 
Explanation: Melatonin