Photoelectric emission is observed from a metallic surface for frequencies \[{{\nu }_{1}}\] and \[{{\nu }_{2}}\] of the incident light rays \[({{\nu }_{1}}>{{\nu }_{2}})\]. If the maximum values of kinetic energy of the photoelectrons emitted in the two cases are in the ratio of \[1:k\], then the threshold frequency of the metallic surface is [EAMCET (Engg.) 2001]

• A.             \[\frac{{{\nu }_{1}}-{{\nu }_{2}}}{k-1}\]                      
• B.            \[\frac{k{{\nu }_{1}}-{{\nu }_{2}}}{k-1}\]
• C.            \[\frac{k{{\nu }_{2}}-{{\nu }_{1}}}{k-1}\]                     
• D.            \[\frac{{{\nu }_{2}}-{{\nu }_{1}}}{k}\]