This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: FMGE 2019, Subject name: ENT
What is the most common cause of deafness in a patient of Nasopharyngeal Carcinoma: 
Select and explain. 
A. Metastasis to Temporal Bone, B. Middle ear Infection, C. Serous otitis media, D. Infiltration of Tumour middle ear
C: Serous otitis media
Answer: C: Serous otitis media 
Explanation: Nasopharyngeal carcinoma Due to obstruction of eustachian tube , there is serous otitis media and leads to hearing loss. M/C site of origin - Fossa of Rosenmuller M/C type - Squamous cell carcinoma M/C Presentation - cervical lymphadenopathy (Neck Mass)