Two Variables Are Said to Have a Direct Relationship If,after

Two variables are said to have a direct relationship if,after controlling for a third variable,the bivariate relationship is the same for all partial tables and

A) the same as in the bivariate table.
B) very different from the bivariate table.
C) each partial table is different from the bivariate table.
D) each partial table is different from every other partial table.