What is the correct response if the craftmaster notices unmovable FOD?

The correct response to unmovable Foreign Object Debris (FOD) is to stop all operations. This is critical because unmovable FOD poses a significant safety hazard on the ramp, potentially leading to incidents that could endanger personnel, damage aircraft, or disrupt operations. By halting all activities, you enable a thorough assessment and removal of the FOD, ensuring that everyone remains safe and that the ramp area is secure for operations to resume safely. Stopping operations is a proactive measure to mitigate any risks associated with the presence of FOD, prioritizing safety above all else during ramp operations.