An Airborne Radar Unit may serve as what in relation to an MRU?

The correct answer is that an Airborne Radar Unit may serve as an extension in relation to a Mobile Radar Unit (MRU). This means that while the MRU provides a core capability for radar detection and tracking, the Airborne Radar Unit enhances this capability by providing an additional layer of surveillance. The airborne unit can operate at different altitudes and can cover a wider area, which allows it to complement the ground-based MRU by extending its operational reach and effectiveness.

This collaborative relationship between the two types of radar systems can result in improved situational awareness and better data fusion, which is essential for intelligence, surveillance, and reconnaissance missions. The airborne unit can also maneuver quickly, offering a degree of flexibility that a stationary MRU cannot provide, thus serving as an extension of the overall radar capability.