A. From the Azure Active Directory admin center, modify the External collaboration settings to include fabrikam.com only.
B. From the Microsoft 365 admin center, modify the Office 365 groups settings.
C. From the External access settings in the Microsoft Teams admin center, add fabrikam.com to the Allowed list of domains.
D. From the Microsoft Teams admin center, turn off org-wide guest access and manually add guest users from fabrikam.com to teams.
Explanation:
https://docs.microsoft.com/en-us/azure/active-directory/b2b/delegate-invitations https://docs.microsoft.com/en-us/microsoftteams/manage-external-access https://docs.microsoft.com/en-us/azure/active-directory/b2b/allow-deny-list