Which special instruction refers to controlling the firing sequence?

The correct choice regarding the special instruction that refers to controlling the firing sequence is associated with maintaining safety and operational readiness. The phrase "Do not load" is a command that often indicates when a weapon system should not be loaded with ammunition. This serves an essential function in controlling the firing sequence because it effectively prevents the crew from inadvertently firing the weapon when conditions are unsafe or when specific operational protocols are in place.

Controlling the firing sequence is critical for ensuring that each action taken by the cannon crew is deliberate and follows established safety measures. When the command "Do not load" is in effect, it implies that the crew should remain vigilant about the status of the weapon system, preventing an unauthorized or unsafe firing scenario. This command is crucial during both safety checks and preparations for fire missions to ensure that all personnel are aware of the weapon’s state and conditions regarding engagement.

In contrast, the other options refer to different concepts related to artillery operations. For example, "Action azimuth" relates to the directional aspect of aiming the weapon, while "Use gunners quadrant" focuses on the specific equipment used for adjusting elevation. "Sweep and zone" pertains to ensuring that the area surrounding the target is clear, which does not directly manage the firing sequence. Thus