What is the third step to share the "Facebook Photos" folder according to the least privilege principle?

Granting only the necessary NTFS permission aligns with the least privilege principle, which is a fundamental concept in security that ensures users and systems have the minimum level of access required to perform their tasks.

When sharing a folder like "Facebook Photos," it's crucial to restrict access to only those individuals who need it and to limit what they can do with the files within that folder. By assigning only the necessary NTFS permissions, you ensure that users can perform their required actions—such as viewing or editing files—without exposing the folder to unnecessary risks, such as deletion or modification by unauthorized individuals. This approach minimizes the potential for accidental or malicious changes to the files.

The other options do not adhere to the least privilege principle. For example, allowing full control to everyone would grant excessive access that could lead to data breaches or loss. Similarly, sharing the folder with read permissions only may not meet all users' needs and doesn’t account for specific permissions that might be necessary for particular users. While deleting unnecessary files could declutter the folder, it does not relate directly to managing access permissions. Thus, granting only the necessary NTFS permission is the most appropriate step in maintaining security and stability in the shared environment.