Explanation: DGPS stands for Differential Global Positioning System. It's an enhancement to standard GPS that provides improved position accuracy. Standard GPS signals can be affected by various factors like atmospheric conditions, satellite clock errors, and signal multipath, leading to inaccuracies. DGPS addresses this by using a network of fixed ground-based reference stations, whose exact locations are precisely known. Each reference station calculates the difference between its known position and the position calculated from the GPS signals it receives—this difference is the "error." These reference stations then broadcast these real-time "differential" correction factors (often via radio beacons, cellular, or the internet) to DGPS-enabled GPS receivers in the vicinity. The user's receiver applies these corrections to its own GPS calculations, significantly improving the accuracy of its position solution, often down to a few meters or less. Therefore, DGPS is fundamentally **B) A system to provide additional correction factors to improve position accuracy.** * **A) Digital Ground Position System** is not the correct acronym or description. * **C) Correction signals transmitted by satellite** is incorrect; DGPS corrections are typically broadcast from ground stations, not the GPS satellites themselves (which transmit the original positioning signals). * **D) A system for providing altitude corrections for aircraft** is too specific. While DGPS improves altitude accuracy and can be used by aircraft, its primary function is overall positional accuracy for many applications, not solely altitude or aircraft specific.