HOTSPOT
An organization prepares to migrate to Office 365. The organization has one domain controller named NYCDC1 and one server named NYC-DS that is designated as the directory synchronization computer.
The organization has the following servers:
You plan to upgrade the servers to support directory synchronization.
You must upgrade each server to meet only the minimum requirements by using the least amount of
administrative effort.
You need to ensure that you can use the Azure AD Connect to synchronize the local Active Directory with Office
365.
What should you do? Select the correct action from each list in the answer area.
Hot Area:
Answer: 
Explanation:
The minimum forest functional level requirement for Office356 is Windows Server 2003.
The minimum domain controller requirement for office 356 is 32-bit Windows Server 2003 Standard Edition with
Service Pack 1 (SP1). From the available options, the minimum requirement is met by Windows Server 2008
R2 Standard Edition.http://msdn.microsoft.com/en-us/library/azure/jj151831.aspx
This is a trick question. Dirsync can only be run on Windows server 2008 R2 or later -> https://oddytee.wordpress.com/2014/03/11/requirements-for-dirsync/. Windows server 2008 R2 is the first 64 bit OS from Microsoft.
In the second box, the correct option are the first: Install the 64 bits version…..
Surely in the second box it’s the first option?
It’s a tricky question, keep in mind that they are asking to use the less administrative effort so if you install the 64 Bit version of Win Server 2008 then you must also apply hotfix KB2386717, on the other hand, you can not install win server 2008 r2 in a 32 bit based hardware because that S.O is only available in 64 bit architecture.
https://docs.microsoft.com/en-us/azure/active-directory/connect/active-directory-aadconnect-prerequisites