How does increasing the distance between charged objects affect the electric force between them?

a- The electric force increases because the distance has an indirect relationship to the force.
b- The electric force increases because the distance has a direct relationship to the force.
c- The electric force decreases because the distance has a direct relationship to the force.
d- The electric force decreases because the distance has an indirect relationship to the force.

d- The electric force decreases because the distance has an indirect relationship to the force.