Supreme White, without a doubt. It’s far more interesting, and out of the ordinary, than the other two.

Edited to add: I would select a different backsplash. Carrera marble as a backsplash, is so overdone, and is too busy with your slab choices.

Don't marry that backsplash yet! I would pick the slab that you like the best, install it first and then go on a few dates with some different backsplashes. Look at your photos, the cabinet sample appears yellow, white and grey in the different photos. The color of your slab will also change once it is inside and seen horizontally. Did you ask them to bring the slabs inside? When I narrowed down my choices I asked to view the final slabs indoors and outdoors, to get a better feel for the color variations in different lighting.

If you really love that backsplash then make that your primary choice and use a plain light gray or white Quartz as your counter. Make sure the undertones of your white cabinets are correct or the cabinets will appear yellow or gray.

Or use the same slab material for your counters and backsplash.

I think you have received all sage advice above!

if you really want the carrara backsplash, then pick a carrara countertop. (the other choices you have are like marble anyway)

or, go darker. like a soapstone, or dark gray quartz.

or pick an almost white quartzite or other marble choice. the White cloud would work.

I agree with everyone. The supreme white would look great with a solid white tile.