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: Medicine
Cause of death which is common in case of coma 
Select and explain. 
A. Tongue falling back and obstructing airway, B. Secretions obstructing airway, C. Cardiac arrest, D. Epilepsy
B: Secretions obstructing airway
Answer: B: Secretions obstructing airway 
Explanation: None