This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Ophthalmology
[{'content': 'Chalazion is/are  a) True meibomian cyst  b) Mucous cyst  c) Sebaceous cyst  d) Cyst of hair follicle  e) Obstruction of meibomian gland \nSelect and explain. \nA. ace, B. abc, C. abd, D. bcd', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Chalazion is chronic non-infective lipogranulomatous inflammation of meibomian gland, a modified sebaceous gland, due to obstruction of duct of meibomian gland.\nChalazion is also called sebaceous cyst of the eyelid.', 'role': 'assistant'}]