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
Masticator space infection usually results from: 
Select and explain. 
A. Infections of the last two lower molar, B. Non aseptic technique in local anaesthesia, C. External or internal trauma to the mandibular angle region, D. All of the above
D: All of the above
Answer: D: All of the above 
Explanation: None