Option C is correct because an Artifact is intended for substantial, self-contained content that users need to view, edit, iterate on, and reuse separately from the surrounding conversation. A landing-page mockup or interactive prototype benefits from a dedicated workspace where the rendered result can be inspected while the team requests targeted revisions to structure, copy, components, or behavior.

Option A confuses prototype production with external research. Research may help collect competitor evidence before design begins, but it does not provide the most appropriate final workspace for the prototype itself. Option B leaves the content embedded in conversational history, making iteration and sharing less convenient and obscuring which version is current. Option D may be useful for preserving reusable project context, instructions, and reference documents, but a Project containing meeting notes is not itself the output format for an interactive mockup.

Projects and Artifacts can be complementary. A Project can maintain design requirements, brand guidance, and research across conversations, while an Artifact contains the evolving prototype. The requested deliverable is standalone, editable, visual, and intended for repeated refinement; therefore, an Artifact directly matches the task.

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