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': "Stem cells are present where in cornea - \nSelect and explain. \nA. Limbus, B. Stroma, C. Epithelium, D. Descmet's membrane", 'role': 'user'}, {'content': 'Answer: A \nExplanation: Answer- A. LimbusLimbal stem cells (also called corneal epithelial stem cells) are stem cells located in the basal epithelial layer of the corneal limbus.Proliferation of limbal stem cells maintains the cornea; for example, replacing cells that are lost tears.Limbal stem cells also prevent the conjunctivalepithelial cells from migrating onto the surface ofthe cornea.', 'role': 'assistant'}]