The administration of a hybrid deployment that connects on-premises Exchange Server with Exchange Online, enabling seamless integration and centralized control.
Well those two things arent related, but if you route all your outbound mail through Office 365, you can leverage DKIM and with your valid SPF record any messages sent from Exchange Online user mailboxes will pass DMARC
If you choose Hybrid or if all your mailboxes are in Exchange Online, it doesn't matter. As long as all the outbound mail routes through Office 365 then you are good.