The bob of a simple pendulum of length $L$ is released from a position of small angular displacement $\theta$. Its linear displacement at time $t$ is ($g =$ acceleration due to gravity).

• A
  $L \theta \cos \left[\sqrt{\frac{g}{L}} \cdot t\right]$
• B
  $L \theta \sin \left[2 \pi \sqrt{\frac{g}{L}} \cdot t\right]$
• C
  $L \theta \cos \left[2 \pi \sqrt{\frac{g}{L}} \cdot t\right]$
• D
  $L \theta \sin \left[\sqrt{\frac{g}{L}} \cdot t\right]$