HOTSPOT
You have an Active Directory forest named contoso.com that contains an Exchange Server 2016 organization
named Contoso.
Contoso.com has a two-way forest trust with an Active Directory forest named fabrika.com. The fabriakm.com
forest contains an Exchange Server 2016 organization named Fabrikam.
You need to ensure that the users in Contoso can access the free/busy information of all the users in Fabrikam.
An administrator from Fabrikam runs the following command in the organization.
Get-MailboxServer | Add-ADPermission –Accessrights Extendedright –Extendedrights “ms-Exch-EPI-TokenSerialization” –User “CONTOSO\\Exchange Servers”
What command should you run in Contoso? To answer, select the appropriate options in the answer area.
Hot Area:
Answer: 
Explanation:
https://technet.microsoft.com/en-us/library/bb124122(v=exchg.160).aspx
Refer to –
https://technet.microsoft.com/en-us/library/bb125182(v=exchg.160).aspx
Ex 2007’s but still hold good for this scenario–
https://blogs.technet.microsoft.com/exchange/2011/03/04/how-to-configure-the-availability-service-for-cross-forest-topologies/
In simple terms..
For a trusted configuration.. use ADD-ADpermission for the target Service Account
For a non-trusted configuration Set-AvailabilityConfig for the OrgWide Free/Busy sharing
Add-AvailabilityAddressSpace -ForestName example.com -AccessMethod PerUserFB -Credentials (Get-Credential)
For a trusted forest:
https://technet.microsoft.com/en-us/library/bb124122(v=exchg.160).aspx
oops, of course -AccessMethod OrgWideFB
Ooops, I see your point now. Sorry to correct you below. Looks like we agree on the answer provided!