A rope of mass $$M$$ and length $$L$$ hangs vertically. Time needed for a transverse pulse to travel from its bottom end to the support is

A

$$\frac{2L}{g}$$

B

$$\sqrt{\frac{2L}{g}}$$

C

$$\sqrt{\frac{L}{g}}$$

D

$$\sqrt{\frac{L}{2g}}$$