Your company has a Microsoft Entra tenant that contains the users shown in the following...

 Create guest user accounts: User1, User2, and User3 only

User1: Privileged Role Administrator role has the ability to manage role assignments in Microsoft Entra ID, including creating guest accounts.

User2: User Administrator role can manage user accounts, including creating guest accounts.

User3: Security Administrator role does not typically include permissions for creating guest accounts, but in some configurations, they might have limited guest user management capabilities.

 Add User3 to Admin1: User2 only

User2: User Administrator role has the permissions to add users to security groups like Admin1.