A positively charged rod is brought close to, but does not touch, an uncharged metal sphere. The sphere is then connected to earth for a short time. The rod is taken away. Which statement about the charge on the sphere is correct?
- AIt is charged negatively because negative charges have moved from earth to the sphere.
- BIt is charged negatively because positive charges have moved from the sphere to earth.
- CIt is charged positively because negative charges have moved from the sphere to earth.
- DIt is charged positively because positive charges have moved to earth from the sphere.