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: ENT
What will be the most likely diagnosis in a 70 year old male with hypo-aesthesia of external auditory meatus (Histelberg's sign positive)? 
Select and explain. 
A. Mastoiditis, B. Bells palsy, C. Vestibular schwannoma, D. Middle ear cholesteatoma
C: Vestibular schwannoma
Answer: C: Vestibular schwannoma 
Explanation: Hitzelberg's sign refers to hypo-aesthesia of the posterosuperior aspect of the external meatus. It is due to involvement of nervus intermedius (sensory root of VIIth nerve).