The correct expression for the time period (T) of a particle of mass (m) performing Simple Harmonic Motion, where k is a constant, is ______.

A

$$T = 2 \pi \surd(k/m)$$

B

$$T = 2 \pi (m/k)2$$

C

$$T = 2 \pi (k/m)2$$

D

$$T = 2 \pi \surd(m/k)$$