Answer:
The correct answer to the question: Which force is exerted by Earth on the satellite, would be, gravity.
Step-by-step explanation:
The force of gravity, and how much power it has over space objects, depends entirely on mass. So, in this case, we have Earth, whose mass is much bigger than that of the far-away satellite, and the other satellite. Due to this, the gravitational force generated by Earth is much higher, and much more powerful, than the one exerted by the other satellite. This is why the astronomer notices that the distant satellite seems to respond more to the force generated by Earth, than the one generated by the satellite that is closer to the other one. This is the reason why satellites such as the moon turns around Earth, and doesn´t go closer to planets such as Mars, or Venus. Because Earth´s mass makes gravitational force higher, and thus the moon stays near Earth.