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
Dense cortical bone used for implant placement is found
in: 
Select and explain. 
A. Anteiror mandible, B. Posterior mandible, C. Anterior maxilla, D. Posterior maxilla
A: Anteiror mandible
Answer: A: Anteiror mandible 
Explanation: None