Generally, the elements of drama that reveal the traits and motivations of the character to the audience are plot and dialogue, but other elements may do this as well.
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.
I would say D is more appropriate. It's possible she has interest, and that is the root of her observations, but adoration is clear by her vivid, positive description.
