GNSS accuracy can be augmented using which of the following networks?

The answer is comprehensive because all the listed networks—Wide Area Augmentation Service (WAAS), International GNSS, and Global Differential GPS—are designed to enhance the accuracy of GNSS (Global Navigation Satellite Systems).

Wide Area Augmentation Service (WAAS) provides correction signals specifically to improve the accuracy of GPS in North America. It uses a network of ground reference stations to monitor GPS signals and sends correction information to users, allowing for greater precision.

International GNSS includes various systems that operate together globally, using different satellite constellations and combinations to provide improved positioning accuracy and reliability over larger areas.

Global Differential GPS (DGPS) refers to a method used to enhance the accuracy of GNSS positioning by using differential stations to transmit corrections for the satellite signals. This technique significantly reduces errors caused by atmospheric interferences, satellite orbit errors, and other factors.

Since all of these networks serve to augment GNSS accuracy in different contexts and capacities, the collective improvement they provide justifies the response. Thus, choosing "All of the above" reflects a thorough understanding of how these various augmentation services contribute to enhanced navigational accuracy.