Provide your best answer for the following question. Give ONLY the answer, no other words or explanation.
For example:

Answer: <most likely answer, as short as possible; not a complete sentence, just the answer!>.

The question is: An object has a weight of 10 kg on the surface of Earth. If the same object were transported to the surface of Mars, the object would have a weight of 3.8 kg. Which best explains why the weight of the object changed when transported from Earth to Mars?
Gravitational force is greater on Earth than it is on Mars.
Difference in gravitational forces.