De or het tbs-instelling?

The correct Dutch article is:

de tbs-instelling

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

How to use tbs-instelling

the tbs-instellingde tbs-instelling
this tbs-instellingdeze tbs-instelling
that tbs-instellingdie tbs-instelling
our tbs-instellingonze tbs-instelling
your tbs-instellingjouw tbs-instelling
every tbs-instellingelke tbs-instelling
which tbs-instelling?welke tbs-instelling?
a big tbs-instelling / the big tbs-instellingeen grote tbs-instelling, de grote tbs-instelling