You have a mess. Only the partition holding the System boot files should be marked Active.
Probably because data drives had been marked Active and you didn't unplug the other HD's when installing, the System boot files were derailed to Disk 3 which doesn't even hold an OS.
When you have separate HD's the best way to Multi Boot is to unplug all other HD's during install, then afterwards plug them back in and boot the other Windows 7 OS by using the one-time BIOS Boot Menu key. This keeps them independent to come and go as you please.
To sort this out, first mark C and E Active: Partition - Mark as Active (Method Two)
Next mark all partitions except E and C Inactive. Partition - Mark as Active,
power down to unplug all other HD's except C, reboot into BIOS setup to set C first HD to boot (after DVD drive), boot it's installer's System Recovery Options
to run Startup Repair 3 Separate Times
until Windows 7 starts and holds the System Active flags.
Now power down (always) to unplug C, plug in E and repeat the same process with it's installer until it starts and holds System Active flags.
Now you can plug in the other HD's. E will boot by default, so when you want to boot into C tap the one-time BIOS Boot Menu key (F8 on most Asus's) to trigger it to boot. If you find you don't like this arrangement, install EasyBCD to default HD OS to add the other to a WIndows Dual Boot.