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: Surgery
The anatomical landmark used during posterior superior alveolar nerve block are mucobuccal fold, occlusal plane, coronoid process and anterior border of: 
Select and explain. 
A. Ramus, B. Mandible, C. Premolar, D. Midline
A: Ramus
Answer: A: Ramus 
Explanation: None