The stopping potential for photoelectrons from a metal surface is $V_{1}$ when monochromatic light of frequency $v_{1}$ is incident on it. The stopping potential becomes $V_{2}$ when monochromatic light of another frequency is incident on the same metal surface. If $h$ is the Planck's constant and $e$ is the charge of an electron, then the frequency of light in the second case is

• A
  $v_{1}-\frac{e}{h}(V_{2}+V_{1})$
• B
  $v_{1}+\frac{e}{h}(V_{2}+V_{1})$
• C
  $v_{1}-\frac{e}{h}(V_{2}-V_{1})$
• D
  $v_{1}+\frac{e}{h}(V_{2}-V_{1})$