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
[{'content': 'What is the most common cause of deafness in a patient of Nasopharyngeal Carcinoma: \nSelect and explain. \nA. Metastasis to Temporal Bone, B. Middle ear Infection, C. Serous otitis media, D. Infiltration of Tumour middle ear', 'role': 'user'}, {'content': 'Answer: C \nExplanation: 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)', 'role': 'assistant'}]