You have a Microsoft 365 tenant that contains Microsoft Exchange Online.

You plan to enable calendar sharing with a partner organization named adatum.com. The partner organization also has a Microsoft 365 tenant.

You need to ensure that the calendar of every user is available to the users in adatum.com immediately.

What should you do?

A. From the Exchange admin center, create a sharing policy.

B. From the Exchange admin center, create a new organization relationship.

C. From the Microsoft 365 admin center, modify the Organization profile settings.
D. From the Microsoft 365 admin center, configure external site sharing.

References:
https://docs.microsoft.com/en-us/exchange/sharing/organization-relationships/create-an-organization-relationship