An example of an expendable supply item is?

The correct choice is a pencil, which qualifies as an expendable supply item due to its nature and intended use. Expendable items are those that are used up or consumed during operations and do not require maintenance or repair. A pencil, for example, is used for writing or making notes and is typically discarded once it has been used up or worn down.

In contrast, the other options are considered non-expendable. Paper is consumable as well, but it is often grouped with other supplies that may not be specifically categorized as expendable in certain contexts. A toolbox is a durable item designed for maintenance and repair, meaning it is expected to be reused many times. A uniform, while it may wear out over time, is not used in a way that contributes directly to an operational task but is instead part of the essential gear for personnel, further indicating its classification as non-expendable. Thus, while all items have their functions, the pencil stands out as an expendable supply due to its single-use nature before needing replacement.