AFS,
to get a C , you need to proove 3 years as a B1 or B2 ...
In France , DGAC will ask you to proove also 1 year as a support staff.
The job of a C , is to check that everything has been approved by a B (i would say that my daughter can do it ...).
Now , if i were you , i would go for a B1B2 (like me) and then after 3 years , if you are interested by hangars job then go for the C.
As Capot said , read the rules mate.
Salut.