A business analyst must standardize how a support Copilot behaves across chats, completes one-off summaries, and reuses approved refund calculations in multiple workflows without duplicating logic. Which distinction among skills, prompts, and instructions should the analyst apply to explain their characteristics?

The correct distinction holds because the scenario demands three different durability patterns: persistent instructions standardize support behavior across chats, single-use prompts complete a bounded one-off summary and then end, and approved skills package refund calculations as versioned reusable capabilities that multiple workflows can invoke without duplicating logic. The session-specific variant fails on persistence because treating instructions as temporary tone adjustments for one conversation cannot standardize behavior across chats, even though its view of prompts and skills reflects real ad hoc customization practice. The single-workflow variant fails on reuse because confining the approved skill to one workflow forces duplication and divergent maintenance, directly violating the requirement to share logic across processes while otherwise correctly describing persistence and single tasks. The reusable-workflow prompt variant fails on execution scope because defining prompts as multi-step reusable workflows confuses one-off task invocation with encapsulated capability reuse, which breaks approval and version control for calculations despite correctly stating persistence and reuse. As an exam caveat, focus on durability and sharing cues such as across chats and without duplicating logic rather than on familiar product labels that often overlap in practice. As a practical check, confirm that behavior rules reside in instructions, the summary lives only in its prompt, and every workflow calls the same skill identifier for refunds.