In a revolver, which part is responsible for holding and aligning the cartridges?

The cylinder is the key component in a revolver that holds and aligns the cartridges. Each chamber within the cylinder is designed to fit a single round, ensuring that the cartridge is properly positioned for firing when the trigger is pulled. The rotation of the cylinder aligns each chamber with the barrel, allowing for a sequential discharge of rounds as the shooter continues to pull the trigger.

Other components listed, like the chamber, typically refer to the specific part within the cylinder where the cartridge is seated but do not encompass the entirety of the component that holds and aligns multiple cartridges. The magwell is associated with semi-automatic firearms and is irrelevant in the context of a revolver, while the slide is a part of semi-automatic pistols and does not apply to revolvers. Understanding the unique design of the revolver helps clarify the pivotal role the cylinder plays in its operation.