What type of guidance system does the Harpoon Guidance System use?

The Harpoon Guidance System utilizes an active guidance system, which is the reason the answer is considered correct. In this context, "active" refers to the capability of the missile to actively seek and track its target using onboard radar. The Harpoon, once launched, emits its own radar signals and processes the echoes returned from the target, adjusting its flight path accordingly to ensure a direct impact. This self-guiding feature allows it to engage targets effectively without needing external illumination or guidance after launch, distinguishing it from other types of guidance systems that rely on external sources or input.

In contrast, passive guidance systems rely on detecting signals or emissions from the target rather than sending out their own; semi-active systems need an external source to illuminate the target for guidance; and inertial guidance systems depend on pre-programmed flight paths and internal navigation without real-time target acquisition. Understanding the distinctions between these systems is crucial for comprehending missile guidance technology and the operational capabilities of weapons like the Harpoon.