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
All of the following are synthetic sharpening stone except: 
Select and explain. 
A. Silicon carbide, B. Alumina, C. Arkansas, D. Diamond
C: Arkansas
Answer: C: Arkansas 
Explanation: Stone type can come in natural or synthetic form:

Natural-Arkansas (preferred)
Synthetic:
	
India stone
Ceramic stone
Composition stone
Diamond
Alumina
Silicon carbide



Nisha Garg, Amit Garg. Textbook of Operative Dentistry.  Edition 3. Page:97