What level does arbok evolve to seviper?

I think you would get an F if you were quizzed on Pokémon. Why do you think it evolves into Seviper? Arbok does not evolve, and Seviper is just a whole different Pokémon. It's ok if you were confused because Jessie used to have an Arbok and she gave it up and got Seviper, and you thought that her Arbok had just evolved. Hope I helped! :)