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
Index areas are 
Select and explain. 
A. Alveolar support areas that disclose the reaction of bone to additional stresses, B. Areas which respond earlier to pathologic changes, C. Alveolar bone areas which respond to treatment, D. None of the above
A: Alveolar support areas that disclose the reaction of bone to additional stresses
Answer: A: Alveolar support areas that disclose the reaction of bone to additional stresses 
Explanation: None