What is the "reverse causality" problem in determining cause and effect?

A) It is a problem that occurs when one concludes that a change in variable X caused a change in variable Y when in actual fact, it is a change in variable Z that caused a change in variable Y.
B) It is a problem that arises when two variables are inter-connected so that a change in variable X causes a change in variable Y, and a change in variable Y causes a change in variable X.
C) It is a problem that occurs when one concludes that a change in variable X caused a change in variable Y when in actual fact, it is a change in variable Y that caused a change in variable X.
D) It is a problem that occurs when one observes that a change in variable X caused a change in variable Y which caused a change in variable Z and concludes that a change in variable X caused a change in variable Z.

C