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: Pharmacology
The dentist who first used Nitrous oxide for the abolition of pain due to dental extraction was 
Select and explain. 
A. Harper David, B. Harvey william, C. Horace wells, D. Hunter John
C: Horace wells
Answer: C: Horace wells 
Explanation: None