De or het moslimactivist?

The correct Dutch article is:

de moslimactivist

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

How to use moslimactivist

the moslimactivistde moslimactivist
this moslimactivistdeze moslimactivist
that moslimactivistdie moslimactivist
our moslimactivistonze moslimactivist
your moslimactivistjouw moslimactivist
every moslimactivistelke moslimactivist
which moslimactivist?welke moslimactivist?
a big moslimactivist / the big moslimactivisteen grote moslimactivist, de grote moslimactivist