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
Most common LMN cause of Facial nerve palsy is? 
Select and explain. 
A. Trauma, B. Bell's palsy, C. Infections, D. Vascular causes
B: Bell's palsy
Answer: B: Bell's palsy 
Explanation: *one of the most common cause of facial weakness is bell's palsy ,a lower motor neuron lesion of the 7th (facial)nerve ,effecting all ages and both sexes *here the lesion is within the facial canal . Ref Harrison20th editionpg 1082-1083