What should be communicated if a unit has completed its previous task?

When a unit has completed its previous task, it is essential to clearly communicate that the last assignment has been finished. This communication serves multiple purposes; it informs the command or dispatch that the unit is available for new tasks, it ensures that there is a clear understanding of the unit's status, and it keeps everyone in the loop regarding current workloads. "Finished last assignment" conveys a straightforward and standardized message that can be easily understood by all involved parties.

This direct communication is crucial in maintaining effective operations, as it allows for better coordination among units and efficient allocation of resources. While the other options may relate to specific procedures or operational statuses, they do not specifically address the need to communicate the completion of tasks in the same direct and clear manner.