De or het winstverdubbeling?

The correct Dutch article is:

de winstverdubbeling

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

How to use winstverdubbeling

the winstverdubbelingde winstverdubbeling
this winstverdubbelingdeze winstverdubbeling
that winstverdubbelingdie winstverdubbeling
our winstverdubbelingonze winstverdubbeling
your winstverdubbelingjouw winstverdubbeling
every winstverdubbelingelke winstverdubbeling
which winstverdubbeling?welke winstverdubbeling?
a big winstverdubbeling / the big winstverdubbelingeen grote winstverdubbeling, de grote winstverdubbeling