For a nomothetic causal relationship to exist, there must be evidence: A. of an empirical correlation between the variables B. that one variable precedes the other in time C. that a third variable did not cause the changes observed in the first two variables D. of an empirical correlation between the variables, one variable precedes the other in time, and a third variable did not cause the changed observed in the first two variables E. of an empirical correlation between the variables and that one variable precedes the other in time