native americans helped the early european COLONISTS.a)DIRECT OBJECT B)INDIRECT OBJECT C)PREPOSITION D)PREDICATE NOMINATIVE. COLONISTS IS A C. I THINK if not please correct

You're still guessing. Go back to the link I gave you in the previous post.

Also, here's a list of prepositions so you can see why this guess is not correct:
http://grammar.ccc.commnet.edu/grammar/preposition_list.htm