Which device aids the guiding of the EGBU besides the laser?

The correct selection highlights the role of the inertial navigation system in aiding the guidance of the EGBU (Electro-Optical Guided Bomb Unit) alongside the laser guidance. The inertial navigation system is crucial as it uses a series of accelerometers and gyroscopes to track the bomb's position, orienting it accurately throughout its trajectory. This system provides continuous data about the bomb's velocity and trajectory, which complements the laser guidance by ensuring the weapon can adjust its path accurately during flight, improving hit accuracy on the intended target.

While other guidance systems such as magnetic, infrared homing, and radar guidance systems have their specific applications in munitions, they are not employed in conjunction with the EGBU. The laser guidance system relies primarily on line-of-sight targeting and requires additional navigation assistance to ensure precision, which is where the inertial navigation system becomes indispensable.