A Semicircular rod is charged uniformly with a total charge $\mathrm{Q}$ coulomb. The electric field intensity at the centre of curvature is $\ldots \ldots \ldots$
(A) $\left[(2 \mathrm{KQ}) /\left(\pi \mathrm{R}^{2}\right)\right]$
(B) $\left[(3 \mathrm{KQ}) /\left(\pi \mathrm{R}^{2}\right)\right]$
(C) $\left[(\mathrm{KQ}) /\left(\pi \mathrm{R}^{2}\right)\right]$
(D) $\left[(4 \mathrm{KQ}) /\left(\pi \mathrm{R}^{2}\right)\right]$