When We Determine That Two Variables Are Correlated, Which of the Following

When we determine that two variables are correlated, which of the following is the best way to think about our observation?

A) Correlation alone does not tell us anything.
B) One of them is causing the other, but we don't know which is which
C) Something interesting is going on, but we need more information.
D) The relationship between the two factors is linear, not curved.