Most starters show some sign of failure prior to being completely inoperative (but not always). Prior to this, was there any change in the starting proceedure? Different noises than before? Intermittent operation? Having to turn the key several times before the starter engaged? These are all signs of a starter that is about to fail.
A clicking starter solenoid is a sign of low current, enough to trigger solenoid, [click on] but not enough the turn starter motor, [click off], so click, click, click, click.
A low battery would cause this.
Poor grounding would cause this.
Poor power connections would cause it.
A bad starter, [short] would cause it.
Try wiggling the transmission shifter in the park slot back and forth and see if the car starts. The car won't start unless it is in park and there is a contact down there which can get dirty.