This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Diseases of orbit, Lids and lacrimal apparatus, Subject name: Ophthalmology
[{'content': 'Mucin layer tear film deficiency occurs in - \nSelect and explain. \nA. Keratoconjunctivitis sicca, B. Lacrimal gland removal, C. Canalicular block, D. Herpetic keratitis', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Also known as sjogrens syndrome or aqueous deficiency dry eye. Ref : ak khurana 6th edition', 'role': 'assistant'}]