This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Ophthalmology
[{'content': 'Extra layer of cilia posterior to grey line \nSelect and explain. \nA. Tylosis, B. Madarosis, C. distichiasis, D. Trichiasis', 'role': 'user'}, {'content': 'Answer: C \nExplanation: REF : AK KHURANA 7TH ED', 'role': 'assistant'}]