How does Block 4 address the challenges posed by GPS-denied environments?

The inclusion of advanced navigation systems that rely on alternative positioning methods is central to addressing the challenges posed by GPS-denied environments. In such scenarios, traditional GPS can be compromised, making it essential for modern fighter systems to have robust alternatives. Block 4 achieves this by integrating technologies such as inertial navigation systems, terrain reference navigation, and other forms of sensor fusion that allow for precise location tracking without dependence on GPS signals. This multi-faceted approach enhances operational flexibility and situational awareness, ensuring that aircraft can continue to navigate effectively, even when GPS is unavailable or unreliable.

The other options suggest limitations on operational capability or reliance solely on existing systems that would not effectively counter GPS-denied scenarios. Therefore, reliance on alternative positioning methods highlights a proactive and technologically advanced strategy, making it a necessary component in modern combat operations.