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: Pathology
Which is not true of Ludwig's angina? 
Select and explain. 
A. Usually arises from an infected molar, B. Involves submandibular space., C. May need emergency tracheostomy, D. None of the above
D: None of the above
Answer: D: None of the above 
Explanation: None