What term describes the act of designing a force to meet a unique task or mission?

The term that best describes the act of designing a force to meet a unique task or mission is "Task-Organizing." This process involves assembling and structuring units into a cohesive force that can effectively tackle specific operational objectives. Task-organizing allows for flexibility in resource allocation and unit composition, enabling commanders to address the unique challenges of each mission, such as varying enemy capabilities or environmental conditions.

In this context, the other terms do not accurately capture the same meaning. For instance, retrograde refers to a tactical movement in a backward direction, typically when a force is withdrawing or retreating from an engagement. Coordinating fires involves the synchronization of artillery and other fire support to achieve effective firepower on a target but does not pertain to the organization of units. Mission-organizing might seem relevant, but it is not a widely recognized term within military doctrine for the specific action of structuring forces for a particular task. Thus, task-organizing is the most precise term for the process described.