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
[{'content': 'All of the following are associated with decreased sense of smell Except \nSelect and explain. \nA. Head trauma, B. Influenza B, C. Parkinsonism, D. Tobacco smoking', 'role': 'user'}, {'content': "Answer: B \nExplanation: Ref: Harrison's principles of Internal Medicine; 20th edition; Chapter 24; Disorders of smell and taste", 'role': 'assistant'}]