When do you start your new art class? vs When do you starting your new art class?

[Lucky Girl]

a)When do you start your new art class? b)When do you starting your new art class?c)When do you are starting your new art class?sentences which one is correct and why?thanks a lot.

[Mister Micawber]

These are correct:

When do you start your new art class?
When are you starting your new art class?
_________________
Native English teacher at Mister Micawber's

[Lucky Girl]

thank sir.why When do you starting your new art class?and When do you are starting your new art class is not suitable?

[Mister Micawber]

They are very wrong.
_________________
Native English teacher at Mister Micawber's

[Supper]