Neither.
They would be aerodynamically loaf-ing on a single ski board.

The first because it gives more up-lift. Source: am skunk skijumper

#1 is the rational choice, but cats are insane, so who knows?

I have a more important question: Would cats have ski jumping in the first place? Humans have snowboarding and skiing out of necessity, because we have 2 legs, we can use them to ride forwards or sideways.
But having 4 legs changes things. From the evidence that we have, 4 legged animals use boards by standing/sitting on them forwards. So I think cats and dogs would definitely invent skate- and snowboarding, but they don't have any necessity to invent skiing. And they might not even see the difference between boards and skis as big enough to warrant a clear distinction. Think about it, the legspan of cats with legs spread akimbo is really short, almost to the point where they can't fail at skiing.

So in my opinion, cats would do ski jumping using snowboards, a far more logical option for them.

I will ask my cat

3rd option: One long one per limb ||||

Second one looks too unstable.

1 for sure

I think the answer is obvious.