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': 'Test of significance for comparing means of 2 group is \nSelect and explain. \nA. Paired t - test, B. Unpaired t - test, C. Sign test, D. Chi - square test', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Paired student t - test\xa0⇒ Comparision of means in paired data of 1 group.\nUn -\xa0Paired student t - test\xa0⇒ Comparision of means between 2 group.\nANOVA test\xa0⇒ Comparision of means if\xa0≥ 3 groups.', 'role': 'assistant'}]