If We Calculate a Correlation Coefficient and We Find That

If we calculate a correlation coefficient and we find that there is a relationship between the two variables,we

A) know that the data must be interval or ratio.
B) know,without referring to the study,that a correlational design was used.
C) can conclude that changes in one variable cause changes in the other variable.
D) cannot conclude that changes in one variable cause changes in the other variable.