If something is "provisional," it can be described as:

The term "provisional" refers to something that is temporary or intended to be used until a more permanent solution is established. In various contexts, such as legal documents, arrangements, or governmental measures, provisional elements are implemented to address immediate needs without making a long-term commitment.

This understanding aligns with the correct answer, which highlights the nature of provisionality as it pertains to being short-term or awaiting a more definitive status. The other options—such as everlasting, supportive, and established—do not convey the essence of temporary or interim conditions that "provisional" embodies. Thus, the selection of "temporary" accurately captures the concept of provisional circumstances.