Block A of mass M in the figure is released from rest when the extension in the spring is ${\mathrm{x}}_0$. The maximum downward displacement of the block is (assume ${\mathrm{x}}_0< \frac{\mathrm{Mg}}{\mathrm{k}}$)

• A

  $2(\frac{\mathrm{Mg}}{\mathrm{k}}-{\mathrm{x}}_0)$

• B

  $\frac{\mathrm{Mg}}{2\mathrm{k}}+{\mathrm{x}}_0$

• C

  $\frac{2\mathrm{Mg}}{\mathrm{k}}-{\mathrm{x}}_0$

• D

  $\frac{2\mathrm{Mg}}{\mathrm{k}}+{\mathrm{x}}_0$