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: Surgery
Halitosisisprimarilybecauseof- Halitosisisprimarilybecauseof- 
Select and explain. 
A. Hydrogen sulfide, B. Alkaline phosphates, C. Trypsin like enzymes Trypsin like enzymes, D. Collagenase enzymeCollagenase enzyme
A: Hydrogen sulfide
Answer: A: Hydrogen sulfide 
Explanation: * Halitosis or unpleasant smell of breath arises mainly from volatile sulfide compounds like- 1) Hydrogen sulfide (H2S). 2) Methyl Mercapton (CH3SH). 3) Dimethyl Sulfide . * Specific character of breath odour is as follows - Rotten Eggs Volatile sulfide compounds Sweet Odour/Smell of dead mice Liver insufficiency Rotten apples Unbalanced insulin dependant diabetes mellitus Fish odour Kidneys insuffiency