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: Dental
Which of the following is the gold standard for testing breath matador (halitosis)? 
Select and explain. 
A. portable volatile sulfide monitor, B. self examination, C. gas chromatography, D. organoleptic rating by a judge
D: organoleptic rating by a judge
Answer: D: organoleptic rating by a judge 
Explanation: None