Explanation:

This question is about creating a one-click policy within Microsoft Purview's Data Security Posture Management for AI portal. These policies are designed to mitigate risks associated with sensitive data and AI websites. The correct configuration for this specific scenario is to select "Test it out first" and apply the policy to "Devices, Instances, and SharePoint sites." This configuration is based on Microsoft's recommended practices for deploying data loss prevention (DLP) and similar policies.
Policy Mode: "Test it out first"
Microsoft recommends using test mode for new policies to evaluate their impact and effectiveness before enforcing them. This approach prevents unintended disruptions to user workflows. In test mode, the policy monitors and audits the specified activities without blocking them. It generates alerts and reports, allowing administrators to review the policy's behavior and make necessary adjustments. This aligns with the principle of "start small, then scale," ensuring that a policy designed to block sensitive data transfers doesn't inadvertently prevent legitimate business activities.
Policy Scope: "Devices, Instances, and SharePoint sites"
The policy aims to block users from pasting or uploading sensitive data to AI websites. This requires a comprehensive scope to cover all potential data exfiltration points.
Devices: This covers the user's local device, preventing data from being uploaded or pasted from applications running on the machine. This is crucial for controlling data from endpoints.
Instances: This refers to SaaS (Software as a Service) instances, including AI websites. Applying the policy to instances ensures that data transfers to these external services are monitored and controlled.
SharePoint sites: Data residing in SharePoint is a common source of sensitive information. Including SharePoint sites in the policy scope ensures that data cannot be directly copied from these locations and uploaded to AI websites, providing a holistic security posture.
By selecting "Devices, Instances, and SharePoint sites," the policy is configured to monitor and protect data across the most common sources and destinations, providing a robust defense against data exfiltration to AI services. This comprehensive approach is a cornerstone of modern data security strategies in Microsoft 365.
This information is verifiable through Microsoft's official documentation for Microsoft Purview, particularly sections related to Data Loss Prevention (DLP) policies and Data Security Posture Management for AI. The best practice of "test first" and the broad scope for sensitive data protection are consistently recommended.