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
Extracted teeth should be preserved in 
Select and explain. 
A. Saline, B. Xylene, C. 10% formalin, D. 10% alcohol
C: 10% formalin
Answer: C: 10% formalin 
Explanation: The teeth used for ground sections should not be allowed to dry out after extraction, because drying makes the hard tissues brittle and the enamel may chip off in the process of grinding. To avoid this, the extracted teeth are preserved in 10% formalin.