A point charge $q$ is surrounded by eight identical charges at distance $r$ as shown in figure. How much work is done by the forces of electrostatic repulsion when the point charge at the centre is removed to infinity?
  • A$0$
  • B$\frac{8 q^2}{4 \pi \varepsilon_0 r}$
  • C$\frac{8 q}{4 \pi \varepsilon_0 r}$
  • D$\frac{64 q^2}{4 \pi \varepsilon_0 r}$
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