The sizing die is ________ and needs to be fitted into an appropriate reloading press.

The correct response emphasizes that the sizing die does not fall into the categories specified in the other options presented. A sizing die is a critical part of the reloading process, and while it may be designed to fit specific cartridges and work with various presses, it is not universally adaptable as the term "universal" might imply.

An adjustable sizing die, for instance, provides the user with the capability to change the size based on the rounds being reloaded, but not all sizing dies offer this feature. The term "manual" could suggest the operational method, but sizing dies themselves are often used in conjunction with automatic or semi-automatic reloading presses as well.

Thus, the appropriate response highlights that a sizing die may not fit neatly into these predefined categories and is better understood as a specialized tool fitted to compatible equipment.