Three particles of each charge $q$ are placed at the vertices of an equilateral triangle of side $L$. The work to be done to decrease the side of the triangle to $\frac{L}{2}$ is

  • A
    $\frac{1}{4 \pi \varepsilon_0} \frac{q^2}{L}$
  • B
    $\frac{1}{4 \pi \varepsilon_0} \frac{2 q^2}{L}$
  • C
    $\frac{1}{4 \pi \varepsilon_0} \frac{3 q^2}{L}$
  • D
    $\frac{1}{4 \pi \varepsilon_0} \frac{3 q^2}{2 L}$

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