Your company has a hybrid deployment of Office 365. All mailboxes are hosted on Office 365. All users access their Office 365 mailbox by using a user account that is hosted on-premises. You need to delete a user account and its associated mailbox. Which tool should you use?

With directory synchronization enabled, the on premise Active Directory becomes the master for all changes to the synchronized mail-enabled objects in Microsoft
Azure Active Directory. You should thus delete accounts from Active Directory and when directory synchronization runs the associated object will be deleted from
Azure and the associated mailbox will be soft-deleted.