Which explosive term describes the component parts necessary for a firing sequence?

The term that best describes the component parts necessary for a firing sequence is "cartridge." In explosive ordnance terminology, a cartridge typically refers to the complete unit that includes not just the explosive material, but also the components that work together to achieve the desired effect upon firing. This includes the projectile, casing, primer, and propellant. Each of these components is crucial in ensuring that the explosive functions correctly, forming a complete system that is intended to be fired in a sequence.

In contrast, while "assembly," "mechanism," and "fuzing" may refer to aspects related to explosives and their operation, they do not encapsulate the entirety of a firing sequence as comprehensively as "cartridge" does. "Assembly" generally relates to the process of putting together the various parts. "Mechanism" pertains to the specific means by which the explosive is activated or initiated. "Fuzing" refers specifically to the device that triggers the detonation of the explosive, which is just one component of the broader firing sequence. Thus, "cartridge" encompasses all necessary components for the firing process, making it the most accurate choice in this context.