This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: C.N.S, Subject name: Medicine
All of the following are associated with decreased sense of smell Except 
Select and explain. 
A. Head trauma, B. Influenza B, C. Parkinsonism, D. Tobacco smoking
B: Influenza B
Answer: B: Influenza B 
Explanation: Ref: Harrison's principles of Internal Medicine; 20th edition; Chapter 24; Disorders of smell and taste