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
Which of the following is not an indicator of difficult mask ventilation? 
Select and explain. 
A. Patient having history of snoring, B. Patient having beard, C. Old age patient, D. Full set of teeth present
D: Full set of teeth present
Answer: D: Full set of teeth present 
Explanation: None