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: Unknown
[{'content': 'Which among the following is the most common cause of neonatal blindness? \nSelect and explain. \nA. Neisseria gonorrhoeae, B. Chlamydia trachomatis, C. Klebsiella, D. Enterobacter', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ref. The Short Textbook of Pediatrics. Pg 146\n\xa0\nOphthalmia neonatorum (ON)\nPurulent conjunctivitis occurring during the first four weeks of life. T\n\nTwo most common causative agents are Neisseria gonorrhoeae and Chlamydia trachomatis, the former being of more concern here because of its propensity to cause blindness.\nThe eyes of the newborn infant are infected during passage through the birth canal of a mother infected with the causative organisms, and symptoms usually appear within the first three days of life.\nON is an ocular emergency and must be diagnosed and treated as quickly as possible.\n\nThere are three major strategies for the control of ON:\n\nPrevention of the disease by antenatal treatment of infected parents\nProphylaxis at birth\nTreatment of the clinical disease in the newborn.\n\nProphylaxis - 1% tetracycline eye ointment and 1% silver nitrate eye drops are highly effective in prophylaxis.', 'role': 'assistant'}]