Which of the Following Formulas Is the Correct Calculation for the Unconditional

Multiple Choice

Which of the following formulas is the correct calculation for the unconditional correlation between variables X and Y?

A) $\frac { \operatorname { sCov } ( X , Y ) } { N - 1 }$
B) $$\frac { \operatorname { sCov } ( X , Y ) } { \sqrt { N - 1 } }$$
C) $$\frac { s \operatorname { Cov } ( X , Y ) } { \sqrt { s \operatorname { Var } ( X ) s \operatorname { Var } ( Y ) } }$$
D) $\frac { s \operatorname { Cov } ( X , Y ) } { \sqrt { s \operatorname { Var } ( X ) } }$