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: Dental
[{'content': 'Chi square test is used for? \nSelect and explain. \nA. Association between two variables, B. Correlation between two variables, C. Mean comparison of two group, D. S.D. of two variables', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]