This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nutrition and health, Subject name: Social & Preventive Medicine
[{'content': 'Nalgonda technique is related to? \nSelect and explain. \nA. Fluorine, B. Chrlorine, C. Nitrate, D. Nitrites', 'role': 'user'}, {'content': "Answer: A \nExplanation: NEERI DEVELOPED A TECHNIQUE FOR REMOVING FLUORIDE BY CHEMICAL DEFLOURIDATION OF WATER CALLED NALGONDA TECHNIQUE. REF. PARK'S TEXTBOOK OF PREVENTIVE AND SOCIAL MEDICAL 21ST EDITION. PAGE NO - 596", 'role': 'assistant'}]