What needs to be done to allow 10 users to utilize all the Azure AD Premium features?

The correct action to enable 10 users to access all Azure Active Directory (Azure AD) Premium features is to assign a license from the Licenses blade of Azure AD. This step is essential because Azure AD Premium is a subscription-based service that unlocks specific features, including advanced security management, identity protection, conditional access policies, and more.

By assigning the appropriate Azure AD Premium licenses to the users, you ensure they have the necessary permissions and capabilities tied to those features. This process typically involves selecting the users from the Licenses blade and assigning them the Premium licenses directly.

While other options may seem relevant to user management in Azure AD, they do not specifically grant the users access to the Premium features. For instance, inviting users to a group does not inherently provide them with any added privileges or access to features unless those features are connected to that group in a specific context. Modifying directory roles could change a user's permissions, but it does not grant access to the features exclusively tied to Azure AD Premium. Adding an enterprise application may enhance the functionality available to those users, but it won’t provide direct access to Azure AD Premium capabilities.