I would think the answer is c.
If two forces act on an object in the same direction, the net force is equal to the sum of the two forces
Just to give you a sense of scale, Jupiter is 2.5 times more massive than all the rest of the planets in the Solar System combined. Jupiter's diameter is 11.2 times larger than Earth. Jupiter is a very gaseous planet. The temperature of the early solar system explains why the inner planets are rocky and the outer ones are gaseous. As the gases coalesced to form a protosun, the temperature in the solar system rose.