Coefficient of contingency, i.e., c is calculated as

A. $$\frac{{\sqrt {{{\text{X}}^2}} }}{{\text{N}}}$$

B. $$\sqrt {\frac{{{{\text{X}}^2}}}{{\text{N}}}} $$

C. $$\frac{{{{\text{X}}^2}}}{{{\text{N}} + {{\text{X}}^2}}}$$

D. $$\sqrt {\frac{{{{\text{X}}^2}}}{{{\text{N}} + {{\text{X}}^2}}}} $$

Answer: Option D