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': 'Superficial corneal vascularization is caused by? \nSelect and explain. \nA. Contact lens, B. Graft rejection, C. Chemical burn, D. Interstitial keratitis', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., Contact lens & 'to' i.e., Graft rejection Superficial Deep Superficial corneal ulcer Contact lens user Trachoma Rosacea keratitis Phlyctenular keratoconjunctivitis o Cornea graft rejection Interstitial keratitis Disciforrn keratitis Deep corneal ulcer Chemical burns Sclerosing keratitis Viral infection can cause superficial corneal ulcer as well as disciform keratitis.", 'role': 'assistant'}]