Respuesta :
The strength of the gravitational force between two objects depends on two factors, mass and distance. the force of gravity the masses exert on each other. If one of the masses is doubled, the force of gravity between the objects is doubled. increases, the force of gravity decreases.
In your case the answer is the fourth option, the distance between two options. But the gravitational force also depends on the mass of an object.
Hope it helped,
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