A block of mass $$m$$, lying on a smooth horizontal surface, is attached to a spring (of negligible mass) of spring constant $$k$$. The other end of the spring is fixed, as shown in the figure. The block is initially at rest in its equilibrium position. If now the block is pulled with a constant force $$F$$, the maximum speed of the block is:

A

$$\frac{F}{\sqrt{mk}}$$

B

$$\frac{2F}{\sqrt{mk}}$$

C

$$\frac{\pi F}{\sqrt{mk}}$$

D

$$\frac{F}{\pi\sqrt{mk}}$$