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 has least sensation for pain 
Select and explain. 
A. Lips, B. Anterior tongue, C. Gingiva, D. Buccal mucosa
D: Buccal mucosa
Answer: D: Buccal mucosa 
Explanation: None