A particle of mass M is at a distance ‘R’ from the surface of a thin spherical shell of mass M uniformly distributed over its surface, R is the radius of the shell. Now select the correct option.

• A

  Gravitational field and potential both are zero at the centre of the shell. 

• B

  Gravitational potential at the centre is zero but gravitational field is not zero.

• C

  At any point inside the shell only gravitational field is zero. 

• D

  Neither gravitational field nor gravitational potential is zero inside the shell.