A metallic sphere has a charge of $10 \mathrm{\mu C}$. A unit negative charge is brought from A to B both 100 cm away from the sphere but A being east of it while B being on west. The net work done is

• A

  Zero

• B

  $2/10 \mathrm{joule}$

• C

  $-2/10 \mathrm{joule}$

• D

  $-1/10 \mathrm{joule}$