The correct statement that describes the factors affecting gravitational force between two objects is: "Gravitational force between two objects is determined by their masses and the distance between their centers." This is based on Newton's law of universal gravitation, which states that the gravitational force is directly proportional to the product of the masses of the two objects and inversely proportional to the square of the distance between their centers.
The argument that best supports the student's claim is: "If the distance between two objects increases, the gravitational force between the objects will decrease." This is because the gravitational force is inversely proportional to the square of the distance.