Correct Answer:
Explanation/Reference:
Note:
DublinOM1 is an x86 server so we can’t upgrade it to SCOM 2012. So we need to deploy a secondary server (x64)
You upgrade your System Center Operations Manager 2007 R2 management group to System Center 2012 - Operations Manager from a secondary management server when the computer hosting the Operations Manager 2007 R2 root management server (RMS) does not meet the minimum supported configurations for System Center 2012 - Operations Manager. You must first move the agents over to the secondary management server and gateway servers.
Reference: