Answer
The electromagnetic force and gravitational force both have an unlimited range.
Work Step by Step
The strong force has a very small range, such as distances within atomic nuclei. Therefore, the strong force does not have an unlimited range.
Contact forces require two objects to be in contact in order for a contact force to exist. Therefore, contact forces do not have an unlimited range.
The electromagnetic force and gravitational force both have an unlimited range. The magnitude of the force decreases as the distance between objects increases, however, even at very large distances, electromagnetic force and gravitational force are non-zero.
