Final answer:
WRM components are essential items and resources necessary for the operation of a weapon system or combat activity.
Step-by-step explanation:
The correct answer to WRM _______ are directly related to and necessary for a weapon system or combat activity is d) components. War Readiness Material (WRM) components are items and resources that are directly related to and are essential for the operation of a weapon system or the conduct of a combat activity. They include but are not limited to repair parts, munitions, support equipment, and vehicles.