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': 'Most commonly used statistical average - \nSelect and explain. \nA. Mean, B. Median, C. Mode, D. None', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Arithmetic mean \n\nIt is the most commonly used statistical average.\nTo calculate mean, add up the values of all individual observation and then divide by the number of observations.\nThe process of adding together is called summation and is denoted by the sign ∑ or S.\nThe individual observation is denoted by ŋ\nThe mean is denoted by the sign X.\nExample :-', 'role': 'assistant'}]