Alphymus

Which of the following can be used to distinguish a solid ball from a hollow sphere of the same radius and mass?

(A) Measurements of the orbit of a test mass around the object.
(B) Measurements of the time it takes the object to roll down an inclined plane.
(C) Measurements of the tidal forces applied by the object to a liquid body.
(D) Measurements of the behavior of the object as it floats in water.
(E) Measurements of the force applied to the object by a uniform gravitational field.