Final answer:
Both the device's location services need to be enabled and the application must have permission to access location data for tracking to occur. This combination ensures that users have control over their privacy. GPS technology, a feature present in mobile devices, is essential for accurate location tracking.
Step-by-step explanation:
Mobile devices and applications can track your location under certain conditions. The conditions are: 1) Only when the location services are enabled on the device, and 2) Only when the application has permission to access location. Therefore, the correct answer to the question of when mobile devices and applications can track your location is 3) Both A and B. Without both the device's location services being activated and the specific application having the user's permission to access this data, location tracking by that app should be restricted.
Moreover, GPS technology is crucial for the accurate functioning of such location-based services. Developed by the U.S. Department of Defense, GPS relies on signals from satellites to pinpoint a device's location accurately. This technology is now a standard feature in many mobile devices, assisting in navigation for drivers, cyclists, and pedestrians alike. However, there are additional methods through which devices may be tracked, such as cell tower triangulation and being detected by various electronic surveillance tools like 'Stingrays'.