What task is aimed at drawing an enemy's attention away from a principal operation?

The task that is specifically aimed at drawing an enemy's attention away from a principal operation is a diversion. A diversion is a tactical maneuver employed to mislead or distract the enemy, allowing friendly forces to conduct their primary mission without interference. By creating a secondary point of interest or concern, the enemy’s focus is shifted, thereby reducing their capacity to respond effectively to the main operation.

In military operations, executing a successful diversion can involve feints, false attacks, or other forms of subterfuge that make it appear as though a significant effort is being expended in a different area. This can create an opportunity for the main force to achieve its objectives with a reduced risk of detection or opposition, which enhances overall mission success.

Other options, while related to military tactics, do not specifically capture the essence of misdirection or distraction in the same way. Deception, for example, involves misleading the enemy but does not explicitly focus on diverting their attention away from a primary effort. Defeat refers to overcoming or destroying the enemy forces directly, while delay involves slowing down the enemy's actions without necessarily drawing their attention elsewhere. Thus, diversion is the most accurate answer in this context.