Prompt During Update - Not Sure Which Option To Choose

I’m in the middle of a big update, and I see the following prompt:

A new version of the configuration file ‘/usr/share/sddm/scripts/Xsession’ is available, but your version has been modified. Would you like to keep your current version or install the new version?

The options are “Use New Version” and “Keep Old Version.”

Which one do I want, or how should I decide?

Thank you

Whenever you are asked this it’s best to stick with the default choice offered. This should be Keep current version or Keep old version.
If you use the muon updater tool sadly you don’t have the option to take a look at the differences which apt-get in a terminal or other utilities offer you.