Your company purchases Microsoft 365 Copilot for its sales department.

By default, Microsoft 365 Copilot is grounded in your organization’s Microsoft 365 data through Microsoft Graph, and it respects the user’s existing permissions. For “find and summarize information across internal documents,” the most direct default document repositories in Microsoft 365 are SharePoint (team sites and shared libraries) and OneDrive (a user’s work files). That is why C (Microsoft SharePoint) and D (Microsoft OneDrive) are the correct selections. Microsoft explicitly describes Copilot as accessing organizational content via Microsoft Graph, including user documents and related work content.

The other options are not “by default” sources. A (on-premises file share) is not automatically part of Microsoft Graph unless you integrate/migrate content or use connectors to make it discoverable in Microsoft 365 experiences. B (custom CRM) similarly requires an integration approach (for example, Microsoft 365 Copilot connectors / Graph connectors) to index and expose that data for Copilot to use. E (Microsoft Sway) is not a primary default content source for Copilot’s document grounding and is not typically referenced as a core internal document repository compared to SharePoint/OneDrive.

So, for immediate, out-of-the-box internal document discovery and summarization within Microsoft 365, SharePoint + OneDrive are the default answer.