VMDK level exclude data disks

I have a need to just backup the OS drives(C: drives) on our virtualized SQL servers. I tried the "exclude data disks" in the advanced button of the vmware policy.

How does netbackup/vmware determine what the "data disks" are?

I ran a test backup with "exclude data disks" and it got the C:, D:, F:, & T: drives.  Yes...it did exclude the MAIN data disk E: which is what I wanted....but I JUST wanted the C: drive...not the others. In our enviroment..C:=os, D:=pagefile/temp, E:=data, F:=sql logs, T:=sql tempdb.

All systems are windows 2008R2...master, media, client...etc running 7.5.0.3. Vshpere ver = 5.0.0...all datastores are V5.

In vmware all disks are seperate vmdk's. NO independent disks.