De or het klasseverpleging?

The correct Dutch article is:

de klasseverpleging

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

How to use klasseverpleging

the klasseverplegingde klasseverpleging
this klasseverplegingdeze klasseverpleging
that klasseverplegingdie klasseverpleging
our klasseverplegingonze klasseverpleging
your klasseverplegingjouw klasseverpleging
every klasseverplegingelke klasseverpleging
which klasseverpleging?welke klasseverpleging?
a big klasseverpleging / the big klasseverplegingeen grote klasseverpleging, de grote klasseverpleging