This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Conjunctiva, Subject name: Ophthalmology
[{'content': 'Cause of blindness in trachoma- \nSelect and explain. \nA. Scarring, B. Pannus, C. Chronic dacrocystitis, D. Entropion', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Trachoma is a leading cause of preventable blindness worldwide, Conjunctival scarring which may be irregular, star-shaped or linear. Linear scar present in the sulcus subtarsalis is called Arlt&;s line. ref : A K KHURANA text of Ophtalmology,E4, page-64', 'role': 'assistant'}]