Stopping potential for the most energetic electron at a distance of 0.5 m for the target metal in an experiment of photoelectricity is ${\mathrm{V}}_0$ .Then in the same experimental set-up stopping potential at a distance of 1 m from the target metal will be ----  

• A

  $\frac{{\mathrm{V}}_0}{2}$

• B

  $\frac{{\mathrm{V}}_0}{4}$

• C

  ${\mathrm{V}}_0$

• D

  $\frac{{\mathrm{V}}_0}{8}$