A charge particle, having mass m and charge –q is thrown from the center of charged ring, having linear charge density $\lambda$ and radius r fixed in a stationary space, along its axis. The minimum speed v for which it will escape this isolated ring is

• A

  $\sqrt{\frac{q\lambda }{4m{\epsilon }_0}}$

• B

  $\sqrt{\frac{q\lambda }{3m{\epsilon }_0}}$

• C

  $\sqrt{\frac{q\lambda }{2m{\epsilon }_0}}$

• D

  $\sqrt{\frac{q\lambda }{m{\epsilon }_0}}$