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: Social & Preventive Medicine
[{'content': 'When ohotoludine reagent is added to water and if free chuirine is present, what colour will be produced? \nSelect and explain. \nA. Pink, B. Yellow, C. Green, D. Red', 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. is 'b' i.e., Yellow", 'role': 'assistant'}]