Answer:
First choice
Explanation:
A satellite in orbit around Earth experiences only one force: the gravitational attraction exerted by the Earth on it. This force is labelled with . In space, there are no other forces acting on the satellite.
The force of gravity acts as centripetal force, "pulling" the satellite towards the centre of its circular orbit. The inertia of the satellite (which has an initial velocity) tends to keep it moving straight, so the combination of these two effects (inertia and force of gravity) results into the circular motion of the satellite.