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
The correlation coefficient can range from: 
Select and explain. 
A. 0 to + 1, B. 0 to -1, C. -1 to +1., D. 0 to 100
C: -1 to +1.
Answer: C: -1 to +1. 
Explanation: None