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': 'Form the normal bacterial flora of the conjunctiva \nSelect and explain. \nA. Corynebacterium xerosis, B. E. Coli, C. Streptococci, D. All of the above', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans. Corynebacterium xerosis', 'role': 'assistant'}]