Three metal spheres are placed next to each other as shown in the picture. A has two times the mass of B. C has one-third the mass of A. The distance between A and C is half that between A and B. Given these conditions, which statement is true? A) The gravitational force between A and B is one-third that between A and C. B) The gravitational force between A and B is two-thirds that between A and C. C) The gravitational force between A and B is three-eighths that between A and C. D) The gravitational force between A and B is four- sevenths that between A and C.