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
In "Pneumonia Severity Scale", most important factor is - 
Select and explain. 
A. Age, B. Congestive Heart Failure, C. Hypothermia, D. Hyponatremia
A: Age
Answer: A: Age 
Explanation: None