You can set expiration policy only for Office 365 groups in Azure Active Directory (Azure AD). Note: With the increase in usage of Office 365 Groups, administrators and users need a way to clean up unused groups. Expiration policies can help remove inactive groups from the system and make things cleaner. When a group expires, all of its associated services (the mailbox, Planner, SharePoint site, etc.) are also deleted. You can set up a rule for dynamic membership on security groups or Office 365 groups. Incorrect Answers: B, D, E: You can set expiration policy only for Office 365 groups in Azure Active Directory (Azure AD). Reference: https://docs.microsoft.com/en-us/office365/admin/create-groups/office-365-groups-expiration-policy?view=o365-worldwide