If there are light switches at both ends of the run one cable would be NM3-WGUG or something. M first look said UF by lack of paper and the crease/groove in the jacket that indoor wire would not have. I like the idea of pulling the wire from one end & routing back from the other end to a single splice. Phone man used a bryable setup with a canister to enclose the splice and a two-part mix that expanded sealed, and oozed out the ends. Multiple lines in conduit risk inductive coupling/anomalies.
I have nothing bad to say about how the original work was done. I've dug into jobs that were a real 'mess' from the git but lasted for decades w/o failing. This doesn't look like a sticky one at all. If you plan to add anything, now's the time if you're 'going in'. (light sw at both ends, second 110v line, etc) btw, our 'frost depth' is 42" for footings, posts etc. For single UF cable deeper than 10" seems to be plenty from what I've laid/dug in 25 yrs.