This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Conjunctiva, Subject name: Ophthalmology
[{'content': 'Tetracyline ointment for mass prophylaxis- \nSelect and explain. \nA. 0.10%, B. 0.50%, C. 1%, D. 5%', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Tetracyclines:These are broad-spectrum bacteriostatic agents with a considerable action against both gram-positive and gram-negative organisms as well as some fungi, rickettsiae and chlamydiae. This group includes tetracycline, chloetracycline and oxytetracycline. ref: A K KHURANA OPHTALMOLOGY,E4, Page-420', 'role': 'assistant'}]