What defines expendable supplies?

Expendable supplies are defined as items that are consumed during use or become part of another assembly. This includes items such as ammunition, bombs, or other armaments that are used in aircraft operations. Once these items are deployed or utilized, they can no longer be used in their original form, signifying their expendable nature.

The other options describe different types of supplies that do not fall under the definition of expendable supplies. For example, permanent or durable items, which are designed for long-term use, do not match the definition of expendable supplies because they are meant to last and not be consumed. Similarly, items that are kept indefinitely without expiration are not classified as expendable since their use does not result in consumption. Lastly, rented items are temporary in nature and do not become part of an assembly nor are they consumed, making them different from expendable supplies. Overall, the correct answer highlights the fundamental characteristic of expendable supplies—consumption and transformation through use.