Which of the following can authors import into an existing Content Fragment?

Authors can import text files into an existing Content Fragment because Content Fragments are specifically designed to handle structured content, often comprising text that can be reused across various pages or applications. By allowing authors to import text files, it facilitates the easy addition of large amounts of textual data without requiring manual entry, ensuring consistency and efficiency in content management.

While other types of files such as PDFs, images, and audio files may be relevant to content creation or overall project management, they do not fit the structured text framework that Content Fragments are intended to support. Importing these formats would typically require different handling or services outside the direct nature of a Content Fragment, focusing instead on the capabilities of asset management within the AEM environment.