The optimum product combination at given level of resources will be where

A. $$\frac{{\vartriangle {{\text{x}}_2}}}{{\vartriangle {{\text{x}}_1}}} = \frac{{{\text{P}}{{\text{x}}_1}}}{{{\text{P}}{{\text{x}}_2}}}$$

B. $$\frac{{\vartriangle {{\text{y}}_2}}}{{\vartriangle {{\text{y}}_1}}} = \frac{{{\text{P}}{{\text{y}}_1}}}{{{\text{P}}{{\text{y}}_2}}}$$

C. $$\frac{{\vartriangle {{\text{x}}_1}}}{{\vartriangle {{\text{x}}_2}}} = \frac{{{\text{P}}{{\text{x}}_1}}}{{{\text{P}}{{\text{x}}_2}}}$$

D. None of these

Answer: Option B