A pendulum is hung from the roof of a sufficiently high building and is moving freely to and fro like a simple harmonic oscillatar. The acceleration of the bob of the pendulum is 20 $$\frac{m}{s^{2}}$$ at a distance of 5 m*fromithe mean position.The time period of oscillation

A

1 S

B

2 S

C

$$\pi$$ S

D

$$2 \pi$$ S