If you could only have 3 long guns, which would you choose?

Going to have to assume 'Long guns' means centerfire rifles. So that means the 12ga & 22lr don't count. Since a 5.56 & .308 are America's standard M&P cartridges it makes them must haves, in my book at least. Quite honestly there isn't much you can't do with them if you have both. If they don't count either, you still get 3, but only 1 if they do.

Under a strict interpretation of the OP's parameters though, it looks like the only choice for me is a switch barrel 12ga, a switch barrel 22, and a switch barrel rifle. 😆
There are way too many good choices for this but at my age;
6CM pushing 108Es
6.5PRC pushing 140Es
28 Nosler pushing 175Es, 180VLDs, & 195EOLs
These will cover my hunting needs and also good target cartridges in my opinion.
All three of these I have built myself, and load for them as well.

308 LR
270WSM (no recent pictures)

Rationing, the AR's you can find ammo just about anywhere if needed. The 270WSM, it will take down anything in N.A..
Maybe I should pair down my collection. Truthfully, I have my favorites and the others could be framed and hung on a wall. Some are invaluable but for sentimental reasons. I'm not asking for those to be included in the list. But let's say, purely for whimsical gab, that you could only have 3 calibers, any calibers, which would you choose?
30 nosler