Which tactical mission task necessitates the use of fire planning and obstacles to disrupt an enemy’s plans?

The tactical mission task that necessitates the use of fire planning and obstacles to disrupt an enemy’s plans is indeed disrupting. This task focuses on hindering the enemy's ability to maneuver, resupply, or coordinate effectively, thereby causing confusion and disorganization within their ranks.

By employing fire planning, forces can target key enemy locations, threatening their operational capacity and creating uncertainty. The strategic placement of obstacles further serves to channel enemy movements into predetermined pathways, making them more vulnerable to engagement. The goal is to disrupt their operational tempo and deny them the ability to successfully carry out their mission, effectively diminishing their combat effectiveness.

The other tasks, while important in their own right, operate with different objectives. Fixing involves holding an enemy force in place, containing focuses on preventing enemy forces from breaking out or advancing, and destroying seeks to eliminate the enemy forces entirely. Each of these has its unique approach and tactical requirements, but they do not emphasize the intricate balance of fire planning and obstacles in the same way that disrupting does.