Salmon are hatched in freshwater streams, and then they migrate to the ocean. when an adult salmon is ready to mate, it returns to the exact stream where it hatched. what term best applies to this behavior?

This is a behavior called natal homing. In the behavior, the animal uses geomagnetic cues from the earth as a way of finding its way back to the location it was born as a way of spawning or breeding in the same location.