A thin uniform rod of length “L” is bent at its mid point as shown in the figure. The distance of the centre of mass from the point “O” is

• A

  $\frac{\mathrm{L}}{2}\sin \frac{\mathrm{\theta }}{2}$

• B

  $\frac{\mathrm{L}}{2}\cos \frac{\mathrm{\theta }}{2}$

• C

  $\frac{\mathrm{L}}{4}\sin \frac{\mathrm{\theta }}{2}$

• D

  $\frac{\mathrm{L}}{4}\cos \frac{\mathrm{\theta }}{2}$