This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous (Bio-Chemistry), Subject name: Biochemistry
PKU-Ferric chloride test color 
Select and explain. 
A. Emerald green, B. Green brown, C. Purple, D. Navy blue
B: Green brown
Answer: B: Green brown 
Explanation: (B) Green brown > A test for phenylketonuria in which ferric chloride is added to urine & turns the urine blue-green when phenylketonuria is present