Which of the following can directly serve as authentication services for Amazon Workspaces? Choose 3 answers from the options given below

Answer options:

A.AD Connector
B.Microsoft AD hosted on AWS
C.Simple AD
D.DirectConnect

Answer – A,B and C
The AWS documentation mentions the following
Amazon WorkSpaces uses a directory to store and manage information for your WorkSpaces and users. You can use one of the following options:
AD Connector — Use your existing on-premises Microsoft Active Directory. Users can sign into their WorkSpaces using their on-premises credentials and access on-premises resources from their WorkSpaces.
Microsoft AD — Create a Microsoft Active Directory hosted on AWS.
Simple AD — Create a directory that is compatible with Microsoft Active Directory, powered by Samba 4, and hosted on AWS.
Cross trust — Create a trust relationship between your Microsoft AD directory and your on-premises domain.
For more information on AWS Workspaces and Active Directory, please visit the below link:
http://docs.aws.amazon.com/workspaces/latest/adminguide/manage-workspaces-directory.html