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
Which of the following conditions may necessitate
emergency tracheostomy to prevent suffocation 
Select and explain. 
A. Cellulitis, B. Ludwig's angina, C. Cavernous sinus thrombosis, D. Maxillary sinusitis
B: Ludwig's angina
Answer: B: Ludwig's angina 
Explanation: None