A ~ Declarative o<span>f the nature of or making a declaration.</span>"declarative statements"
The correct answer is complement.
Like you wrote above, to complete is when you make something whole. Complement is something that completes your collection. The bronze statue completed her collection perfectly, which is why it was a good complement. Somebody can give her a compliment on her complement, however, meaning that he or she can praise the statue. :)
I think the answer would be C, because an implicit theme is one that's hidden in the story and you kind of have to dig into the piece and look for it.