A company deploys Office 365 in a federated identity model. The environment has two Active Directory Domain
Services (AD DS) servers and two Web Application Proxy servers that are not joined to the domain.
All externally published applications that use Windows Authentication and are hosted on-premises must use
Active Directory Federation Services (AD FS) to log on.
You need deploy pre-authentication on the Web Application Proxy (WAP) servers.
What should you do first?

A.
Enable Kerberos constrained delegation.

B.
Join the WAP servers to the AD DS domain.

C.
Remove and reinstall the AD FS role.

D.
Remove and reinstall the WAP role.