De or het ontvelling?

The correct Dutch article is:

de ontvelling

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

How to use ontvelling

the ontvellingde ontvelling
this ontvellingdeze ontvelling
that ontvellingdie ontvelling
our ontvellingonze ontvelling
your ontvellingjouw ontvelling
every ontvellingelke ontvelling
which ontvelling?welke ontvelling?
a big ontvelling / the big ontvellingeen grote ontvelling, de grote ontvelling