The correct option is C The pole of the earth
As, the earth is not a perfect sphere. The gravity keeps on changing as we move from one place to another. But it is maximum at the place where it is nearer to the centre. Earths gravity is the maximum at the poles because the Earth is kind of an ellipse (not a perfect sphere) And the equator is further away from the centre of mass of the Earth than at the poles.
hence, option C is correct.