De or het alcoholpreventie?

The correct Dutch article is:

de alcoholpreventie

Rule Words ending in -tie and -sie: almost always de. See the rule

How to use alcoholpreventie

the alcoholpreventiede alcoholpreventie
this alcoholpreventiedeze alcoholpreventie
that alcoholpreventiedie alcoholpreventie
our alcoholpreventieonze alcoholpreventie
your alcoholpreventiejouw alcoholpreventie
every alcoholpreventieelke alcoholpreventie
which alcoholpreventie?welke alcoholpreventie?
a big alcoholpreventie / the big alcoholpreventieeen grote alcoholpreventie, de grote alcoholpreventie