The most current, which for your 3DS it should be Ver. 9.8.0-25U while Version 1.4 for your Omega Ruby should be the most current.
To check and see if your 3DS is up to date just go to the system settings, the click "Other Setting", go to page four, then click System Update.
Your Omega Ruby will let you know if there's an update available when you attempt to play it.
Source: My 3DS and Alpha Sapphire
Hopefully I've Helped!