This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Biostatistics, Subject name: Social & Preventive Medicine
[{'content': 'Strong correlation is signified by a correlation coefficient of ? \nSelect and explain. \nA. Zero, B. 1, C. Less than 1, D. More than 1', 'role': 'user'}, {'content': 'Answer: B \nExplanation: .', 'role': 'assistant'}]