De or het omzetbelastingwetgeving?

The correct Dutch article is:

de omzetbelastingwetgeving

Rule Words ending in -ing: almost always de. See the rule

How to use omzetbelastingwetgeving

the omzetbelastingwetgevingde omzetbelastingwetgeving
this omzetbelastingwetgevingdeze omzetbelastingwetgeving
that omzetbelastingwetgevingdie omzetbelastingwetgeving
our omzetbelastingwetgevingonze omzetbelastingwetgeving
your omzetbelastingwetgevingjouw omzetbelastingwetgeving
every omzetbelastingwetgevingelke omzetbelastingwetgeving
which omzetbelastingwetgeving?welke omzetbelastingwetgeving?
a big omzetbelastingwetgeving / the big omzetbelastingwetgevingeen grote omzetbelastingwetgeving, de grote omzetbelastingwetgeving