Which of the following is NOT a style of muzzleloading firearm?

The correct choice is lever-action, as it does not belong to the category of muzzleloading firearms. Muzzleloading firearms operate on the principle of loading the loose powder and projectile from the muzzle end of the barrel. The caplock, flintlock, and inline percussion styles are all techniques used to ignite the powder charge within muzzleloaders.

Caplock, also known as percussion caplock, utilizes a percussion cap to ignite the powder when the hammer strikes it. Flintlock firearms use a flint mechanism to create a spark that ignites the powder. Inline percussion firearms present a modern adaptation where the ignition system is aligned with the barrel for enhanced performance.

In contrast, lever-action firearms operate using a different loading mechanism that involves a lever to chamber cartridges, which are preloaded ammunition. This action type is commonly associated with centerfire or rimfire firearms, not muzzleloaders, highlighting why it is not considered a style of muzzleloading firearm.