What does the correlation coefficient measure

A)  the central tendency 
B)  the degree of relationship between two variables 
C)  the difference between the largest and smallest scores in a data set 
D)  the amount of variability in a data set

The correlation coefficient measures the degree of relationship between two variables. It tells us how strongly two variables are related and in what direction. It ranges from -1 to +1, where -1 indicates a perfect negative relationship, 0 indicates no relationship, and +1 indicates a perfect positive relationship.