I bought a house a few months ago and I'm still trying to figure out all the wiring. I found these coming out of a cabinet in the kitchen.
I think (?) the black one is a cut-off coax cable. There's a LOT of coax in this house, so that seems straightforward (but I would still love if someone can confirm!)
I'm not sure about the other ones. They don't look electric, as I'd expect electric to be black + white + copper, like the rest of the house.
There is supposedly a speaker system in the house (I see speakers) but I haven't figured it out yet. Could that be power for the speakers? I'm not familiar with speaker wire setup. If it's speakers, why would there be so many wires?
Nice thing about speaker wires since he says he sees speakers still in the house, is you could just connect an audio source and you'll know exactly where that wire ends.